Effects of a methanolic extract and a hyperforin-enriched CO2 extract of Hypericum perforatum on alcohol intake in rats

Hypericum perforatum extracts (HPE) inhibit ethanol intake in rats. Hypericin and hyperforin have been proposed as major active principles of HPE. The present study compared the effect on ethanol intake in alcohol-preferring rats of two Hypericum perforatum extracts: a methanolic extract containing 0.3% hypericin and 3.8% hyperforin (HPE1) and a CO2 extract (HPE2) with 24.33% hyperforin and very low hypericin content. Freely feeding and drinking rats were offered 10% ethanol 2 h/day and HPE were given intragastrically 1 h before access to ethanol. Both extracts dose-dependently reduced ethanol intake, HPE2 being about eight times more potent than HPE1. Food and water intakes were not affected by doses that reduced ethanol intake. HPE2, unlike HPE1, reduced blood-alcohol levels (BAL) at doses of > or = 31.2 mg/kg, whereas the dose of 15.6 mg/kg, which reduced ethanol intake, did not significantly modify BAL; blood-acetaldehyde levels were never increased. As previously observed for HPE1, intracerebroventricular pretreatment with 5,7-dihydroxytryptamine (150 microg/rat) did not affect attenuation of ethanol intake induced by HPE2, but reduced its effect in the forced swimming test (FST). Intraperitoneal pretreatment with the sigma-1 receptor antagonist NE-100 (0.25 mg/kg) did not affect inhibition of ethanol intake induced by HPE1 (250 mg/kg) or HPE2 (125 mg/kg), but abolished the effect of both extracts in the FST. In conclusion, the present results indicate that HPE2 inhibits ethanol intake more potently than HPE1; the higher potency of HPE2 parallels the hyperforin content, suggesting that hyperforin may have an important role in reducing ethanol intake. Moreover, different neurochemical mechanisms are apparently responsible for the reduction of ethanol intake and for the antidepressant-like effect of HPE.     

Thin cutaneous malignant melanomas (< or =1.5 mm): identification of risk factors indicative of progression

BACKGROUND: Although thin cutaneous melanomas generally have a favorable prognosis, in some cases they may undergo progression. The current study was undertaken to identify variables that may predict a more aggressive clinical outcome in these patients. In addition to classic clinicopathologic features, the authors tested the prognostic impact of three new morphometric quantitative parameters: 1) tumor thickness plus regression thickness (T+R), 2) percentage of skin thickness infiltrated by tumor cells (T/S ratio), and 3) percentage of skin thickness infiltrated by tumor cells and regression ([T+R]/S ratio). METHODS: The authors retrospectively evaluated 287 patients with invasive cutaneous melanoma < or = 1.5 mm in thickness. Disease free survival rates (Kaplan-Meier method) were compared by using the log rank test. A multivariate analysis (Cox proportional hazards model) was used to determine the independent effect of each variable on progression. Progression was defined as any documented cutaneous local and/or distant metastasis. RESULTS: Thirty-two of the 287 patients (11.1%) underwent disease progression. The overall 5-year and 10-year disease free survival rates were 89.3% and 84.6%, respectively. In the univariate analysis, the following factors were found to be significant predictors of progression: male gender (P = 0.01), acral-lentiginous histotype (P = 0.02), tumor thickness (P = 0.005), T+R (P = 0.001), T/S ratio > or = 50% (P = 0.03), (T+R)/S ratio > or = 50% (P = 0.006), vertical growth phase (P = 0.04), and absence of inflammatory response (P < 0.0001). Conversely, age, site, and Clark's level did not affect the risk of recurrences and/or metastases significantly. In the multivariate analysis, only T+R (P = 0.009) and inflammatory response (P < 0.0001) were found to be independent predictors of progression. Five-year disease free survival rates according to presence versus absence of inflammatory response were 93.4% and 63.8%, respectively (P < 0.0001). CONCLUSIONS: In the current study, peritumoral and intratumoral inflammatory infiltrate and T+R were found to be strong independent predictors of progression in thin cutaneous melanomas.     

Genetic regulation of alpha-1-antitrypsin levels in the neonatal period: The influence of the PiS allele and the PiM subtypes

Five groups of full-term newborn infants divided on the basis of the subtypes of M and one group of full-term newborn infants belonging to the phenotype M1S have been studied.A decrease in alpha-1-antitrypsin level in the M1S newborn infants was observed (P<0.001). A similar decrease was observed in a group of M1S preterm newborn infants in comparison with M1M1 and M2M2 newborn infants of the same gestational age.Moreover, full-term infants belonging to the subtype M1M2 also showed a decrease in the level of this inhibitor in comparison to the full-term infants belonging to other subtypes of M (P<0.01). Preterm newborn infants belonging to subtypes M1M2 and M1M1 showed identical circulating alpha-1-antitrypsin levels.When the phenotype is taken into account, data obtained from newborn infants free from perinatal pathology show that alpha-1-antitrypsin levels—but not alpha-2-macroglobulin levels—increase with fetal age.Moreover the specific compensatory response to the deficiency, consisting in an increase in alpha-2-macroglobulin levels, is absent in M1S and M1M2 neonates.The wide distribution of the M1M2 subtypes and, in some regions of the MS phenotype, suggests a need for genetic typing of the alpha-1-antitrypsin molecule in investigating the behaviour of this inhibitor in the perinatal period.Supported in part by a grant from Consiglio Nazionale delle Ricerche     

Hypotensive effect in dogs and rats of intravenous injections of the alpha 1-adrenoreceptor antagonist benoxathian

The hypotensive effect of the alpha 1-adrenoreceptor antagonist benoxathian has been evaluated in rats and dogs, in comparison to that evoked by WB 4101 and prazosin. In anaesthetized dogs, i.v. injection of benoxathian (25-100 micrograms/kg), WB 4101 (5-25 micrograms/kg) and prazosin (50 micrograms/kg) produced an immediate fall in diastolic blood pressure, which reached a maximum at about 30 sec after drug administration. Whereas the hypotensive effect of prazosin persisted up to 3 hr following injection, the effect of both benoxathian and WB 4101 completely disappeared after 30-60 min. The hypotensive effect of benoxathian was dose-dependent. Pressor responses to i.v. noradrenaline (5 micrograms/kg), adrenaline (5 micrograms/kg) and phenylephrine (20 micrograms/kg) were markedly inhibited (60-75%) by benoxathian (100 micrograms/kg) whilst the pressor response to angiotensin II (0.05 micrograms/kg) was not reduced, but indeed slightly increased. The hypotensive effect of benoxathian (100 micrograms/kg) was abolished following pre-treatment with prazosin (50 micrograms/kg) or hexamethonium (1000 micrograms/kg). In anaesthetized rats similar results were obtained although recovery in blood pressure from the initial drop after i.v. injection of the drugs was slower than in dogs. Benoxathian was slightly more toxic than WB 4101 in rats. In conclusion, present findings show that benoxathian causes a profound hypotensive effect in dogs and in rats through postsynaptic alpha-adrenoreceptor blockade; however its effect, as well as that of WB 4101, is shorter lasting than that of prazosin.     

Decellularized dermis in combination with cultivated keratinocytes in a short- and long-term animal experimental investigation

Decellularized human dermis as a potentially ideal scaffold for dermal substitution in severe burns was examined in a two‐staged animal experiment. In an initial step, an in vitro generated composite graft consisting of human keratinocytes and decellularized dermis (AlloDerm®) was transplanted onto nude mice in a short‐term trial (n = 20, 14 days). Subsequently, a combined one‐step grafting of full thickness wounds with both decellularized dermis (in part preincubated with fibroblasts) and cultivated autologous keratinocytes as a cell suspension in fibrin glue was done in a long‐term porcine animal model (n = 10, 6 months). In both series, macroscopic wound healing was evaluated by planimetry. Histological investigations included morphological as well as immunohistochemical parameters. The short‐term study showed both successful integration of the composite grafts and reduction of wound contraction compared with the control group (epithelial grafts). The long‐term porcine study displayed reduced myofibroblast formation and contraction in the wounds that had been treated with fibroblast‐preincubated dermis. After 4 weeks, a decline of the structural integrity of the dermal matrix could be noticed. The utility of decellularized dermis as template for both dermal reconstitution and keratinocyte delivery vehicle was shown. The closure of full thickness wounds by a single‐step combination of an autologous keratinocyte fibrin sealant suspension and acellular dermis in a pig animal model could be shown. Incorporation of fibroblasts led to reduced wound contraction but could not prevent the loss of dermal integrity. The engineered ‘skin’ remained viable and stable over a period of 6 months.     

Effect of capsaicin neonatal treatment on the salt intake of the adult rat.

The present study investigated the involvement of capsaicin-sensitive sensory neurons on salt intake control in the rat, following capsaicin neonatal treatment. Capsaicin did not affect salt appetite induced by intramuscular injection of deoxycorticosterone enantate, or by intracranial injection of renin. Moreover, it did not alter salt preference of rats given access to a variety of NaCl concentrations, or the need-free salt intake of multidepleted male rats. On the other hand, in response to furosemide-induced sodium depletion, the salt intake of capsaicin-treated rats was lower than that of controls. However, furosemide-induced Na+ excretion of capsaicin-treated rats proved to be lower than that of controls, thus suggesting that difference in salt intake might be secondary to lower sensitivity of capsaicin-treated rats to the natriuretic action of furosemide. Salt intake is known to be influenced by sensory information from the oral cavity, from the liver and from the intravascular compartment. The absence of effect of capsaicin neonatal treatment suggests that sensory fibers relevant to salt intake control may not be capsaicin sensitive. On the other hand, our findings indicate that capsaicin treatment alters the renal response to furosemide and stimulate further studies on the effects of capsaicin on renal function.