Therapeutic potential of certain drug combinations on paclitaxel-induced peripheral neuropathy in rats.

BACKGROUND AND AIMS: Experimental research and clinical data support the potential combination therapy for the treatment of neuropathic pain. We aimed to investigate the analgesic effect of the following associations: gabapentin + etifoxine; tramadol + etifoxine; gabapentin + tramadol, in an experimental model of peripheral neuropathy induced by paclitaxel. MATERIALS AND METHODS: Neuropathy was induced in male Wistar rats by the daily administration of 2 mg÷kg body weight (bw) paclitaxel intraperitoneally, four days in a row. Analgesics were given concomitantly with paclitaxel, in the following doses: tramadol 15 mg÷kg bw, etifoxine 100 mg÷kg bw, gabapentin 300 mg÷kg bw. Tactile allodynia and mechanical hyperalgesia were assessed using the Dynamic Plantar Aesthesiometer apparatus (Ugo Basile). After 18 days of treatment, the brain and liver tissue susceptibility to lipid peroxidation was evaluated and the sciatic nerve histological examination of the effect on myelin fibers was performed. RESULTS AND CONCLUSIONS: Experimental data have shown a strong analgesic effect of these three tested combinations expressed mainly by the statistically significant increased maximum response time, both in the assessment of allodynia and hyperalgesia. The gabapentin + tramadol combination lead to the maximum analgesic effect, immediately after the discontinuation of paclitaxel (44.94%, p<0.0001) and throughout the study. The treatment associated with tramadol caused a reduction in lipid peroxidation in the brain as compared to paclitaxel group. Combination therapy showed reduced damage to myelinated fiber density in the sciatic nerve. The drug combinations used in the experiment showed therapeutic potential in the fight against neuropathic pain induced by the administration of taxanes.

Pharmacotoxicological screening on new derivatives of beta-phenylethylamine, potential agonists of beta3-adrenergic receptors.

BACKGROUND AND AIMS: Beta3-adrenergic receptors (beta3-ARs) have been initially characterized in 1989. Afterwards, their tissue distribution was established: white and brown adipose tissue, central nervous system, myocardium (atrial and ventricular), blood vessels, smooth gastrointestinal muscles (stomach, small intestine, colon), gallbladder, urinary bladder, prostate, skeletal muscles. Non-clinical trials have demonstrated the major implication of beta3-ARs in glucose metabolism, implicitly, in insulin release, and also in obesity. Therefore, new compounds were synthesized starting from beta-phenylethylamine nucleus and substituted in various positions, for possible antidiabetic and÷or antiobesity action. MATERIALS AND METHODS: In the present research, the antidiabetic action of newly synthesized compounds was investigated on an experimental model of alloxan-induced diabetes, administered in dose of 130 mg÷kg body weight (bw), intraperitoneally (i.p.). After 14 days of treatment, glycemia and enzymes involved in homeostasis of glucose metabolism, glucose-6-phosphate dehydrogenase (G6PD), glucose-6-phosphatase (G6Pase) and hexokinase were determined. Animals were then euthanized and histopathology examinations were performed on harvested liver, kidney, spleen and brain in order to document pathological changes induced by alloxan-induced diabetes and÷or by tested compounds. RESULTS AND CONCLUSIONS: Glycemia in animals treated with the tested compounds decreased statistically significant for groups C2 and C3 (-42.13% and -37.2%, respectively), compared to diabetic control group. C2 was also the compound to favorably modify the dynamics of determined enzymes, together with the display of very good safety profile supported by minor, non-significant, histopathological changes.

Influence of hyperforin on the morphology of internal organs and biochemical parameters, in experimental model in mice.

BACKGROUND AND AIMS: Hyperforin (HY) is used to treat depression and skin irritation and has been shown a number of pharmacological activities. The literature does no cite data on changes that may occur in the body after HY intake (ethylene diammonium salt - EDS) in long-term administration. From this point of view, the present work is a key to determining the pharmacotoxicological profile of the HY-EDS, in long-term administration. MATERIALS AND METHODS: In present research, the influence of toxic doses of HY-EDS was investigated on the biochemical serum parameters and the histopathological changes in internal organs on the experimental mice model. For acute toxicity determination, the HY-EDS was tested in doses of 2000-5000 mg÷kg, administered once per day orally. For subacute toxicity, the HY-EDS was tested in three groups of mice, in doses of 50, 75 and 100 mg÷kg÷day, administered once daily, for 28 consecutive days. RESULTS AND CONCLUSIONS: As concern acute toxicity, a lethal effect has not occurred at any of the two tested doses and HY-EDS was classified as Class V toxic: median lethal dose (LD50) >5000 mg÷kg, p.o. After 14 days of follow-up in acute toxicity, the experimental results showed a statistically significant increase of aspartate transaminase (AST) and alanine transaminase (ALT), compared to the control group. There were no changes in creatinine and serum glucose compared to the control group. After the administration of repeated doses, it was observed an increase of serum transaminases and alkaline phosphatase. Histological examination revealed that the liver injuries were in an initial stage, making them reversible in case of HY-EDS treatment discontinuation. There was no evidence of kidney damage to any of the doses of HY-EDS.

Finasteride adverse effects in subjects with androgenic alopecia: A possible therapeutic approach according to the lateralization process of the brain.

Nowadays, finasteride is a relatively frequently prescribed drug in the therapeutic management of male androgenic alopecia. The reported adverse effects are notable in some patients, consisting in signs and symptoms that are encountered both during finasteride administration and after treatment cessation. Clinical and imagistic data show that cognition and sexuality are two distinct but interrelated environmental functions, most probable due to lateralization process of the brain. Specific for our topic, relatively recent published studies found that frequency and severity of finasteride adverse effects could be interrelated with hand preference and sexual orientation of the respective subjects. This paper tries to explain/support this interrelation through a psychophysiologic approach, to suggest how this premise could be further proved in dermatological practice, and to highlight its relevance in respect to therapeutic approach of male androgenic alopecia. As a possible therapeutic application, subjects having preference for a certain sexual orientation and/or predisposition for a given dominant hand could be advised before finasteride administration, that present an increased risk/sensitivity to develop adverse effects. Finally, even if finasteride and post-finasteride symptoms overlap to a large extent they should be, however, viewed as distinct physiopathologic entities, which could require perhaps different therapeutic approaches.