Absence of leptin secretion compromises reproductive function and fertility in the ob/ob mouse which, when given leptin, shows a rise in serum LH levels and becomes fertile. Recently, the long and active isoform of the leptin receptor was detected in the ovary, indicating that leptin may also show direct gonad-related activity. To examine this, we studied the effect of graded doses of human leptin on estradiol (E2) and progesterone (P4) concentrations in the culture media of human granulosa-lutein cells obtained from follicular fluid of women undergoing in vitro fertilization. We also evaluated the mRNA expression of steroidogenic acute regulatory protein (StAR), aromatase, and cytochrome P450 17alpha (CYP17) in these cells at baseline and after exposure to leptin. Estradiol levels were significantly decreased in the media 24 hours after incubation of the cells with increasing hLeptin concentrations (10(-11) - 10(-7) mol/l). The maximal 30% decrease in E2 production was caused by the 10(-9) mol/l hLeptin concentration; however, P4 levels in the media were not influenced by leptin. Exposure of granulosa-lutein cells to 10(-9) mol/l hLeptin did not produce any measurable changes on StAR, aromatase, or CYP17 mRNA expression. When hLeptin (10(-9) mol/l) was co-incubated with increasing concentrations of hCG (1.25 - 10 mlU/ml), IGF-II (15-60 ng/ml) or 1-6 desaminated IGF-II (deslGF-II; 15-60 ng/ml), it did not modify the elevation of E2 concentrations caused by each of the different stimuli. We conclude that leptin suppresses E2 secretion by human granulosa-lutein cells but does not impair the stimulatory effects of hCG and IGFs on these cells. Leptin may play a minor, but direct regulatory role on unstimulated human ovarian steroidogenesis by interfering with either the translational or post-translational steps of the baseline CYP17 and/or aromatase synthesis and/or the activation of the enzymes.
Background/Aims: Vitamin D deficiency is hypothesized to represent a risk factor in several neoplasms. The aim of this study was to determine whether serum 25-hydroxyvitamin D (25-OHvitD) deficiency represents a risk factor for neuroendocrine neoplasms (NENs) and can be associated with overall survival (OS) and progression-free survival (PFS). Methods: From 2010 to 2015, 138 patients with gastro- entero-pancreatic NENs (61 females; median age, 63 years) were included in the study. Serum 25-OHvitD levels, which were measured at baseline, were defined as deficient if ≤20 ng/mL. In such cases, 25-OHvitD supplementation was administered to the patients. The possible associations between 25-OHvitD levels and disease grading, staging, overall OS, and PFS were considered. Furthermore, the possible association between 25-OHvitD supplementation and PFS or OS was evaluated by Cox proportional hazards regression. Results: Median 25-OHvitD levels were 12.9 ng/mL (range 2-32); in detail, 94 patients (68%) had ≤20 ng/mL, with 46 cases (33%) having ≤10 ng/mL. An inverse correlation was observed between 25-OHvitD levels and OS (p = 0.03, rs = -0.18) and PFS (p = 0.01, rs = -0.22). At Cox proportional hazards regression, mortality was not related to 25-OHvitD levels; however, there was an association between 25-OHvitD supplementation and OS (p < 0.002). Conclusions: Vitamin D deficiency is highly prevalent among NEN patients. 25-OHvitD supplementation potentially plays an important role in the correction of 25-OHvitD values, and has an influence on the clinical outcome. However, further studies are needed to confirm this observation.
BackgroundChronic autoimmune atrophic gastritis (CAAG) is an autoimmune disease characterized by hypo/achlorhydria. A role of CAAG in the pathogenesis of nutritional deficiencies has been reported, therefore we hypothesized a possible association between CAAG and 25-OH-Vitamin D [25(OH)D] deficiency. Aim of the present study is to evaluate the prevalence of 25(OH)D deficiency in CAAG patients. Methods: 87 CAAG patients (71 females; mean age 63.5 ± 12.8 years) followed at our Centre from January 2012 to July 2015 were consecutively evaluated. 25(OH)D, vitamin B12, parathormone, and calcium were measured in all the CAAG patients. The results were compared with a control group of 1232 healthy subjects.ResultsIn the CAAG group the mean 25(OH)D levels were significantly lower than in the control group (18.8 vs. 27.0 ng/ml, p < 0.0001). 25(OH)D levels < 20 ng/ml was observed in 57 patients, while levels < 12.5 ng/ml in 27 patients. A significant correlation between vitamin B12 values at diagnosis and 25(OH)D levels was observed (rs = 0.25, p = 0.01). Interestingly, the CAAG patients with moderate/severe gastric atrophy had lower 25(OH)D values as compared to those with mild atrophy (11.8 vs. 20 ng/ml; p = 0.0047). Moreover, the 25(OH)D levels were significantly lower in CAAG patients with gastric carcinoid as compared to those without gastric carcinoid (11.8 vs. 19.8 ng/ml; p = 0,0041).ConclusionData from the present study showed a significant reduction of 25(OH)D levels in CAAG patients and a possible impairment of vitamin D absorption in CAAG may be postulated. Any implication to the genesis of gastric carcinoids remains to be elucidated.
The annual and daily variations of brain serotonin and 5-hydroxyindolacetic acid have been studied over a 6-year period in normally grouped and isolated mice. The results obtained indicate that differences exist between normally grouped and isolated animals, especially when referred to the annual changes to which brain serotonin and 5-hy-droxyindolacetic acid undergo. The results suggest that the outcome of the experiments on neurochemistry, neuropharmacology and behavior can change according to the month of the year and they can further be modified by differential housing of mice.
Prolonged isolation in mice is known to induce several behavioral changes, among which impairment of learning was also reported. On the other hand, alcohol is known to have either stimulant or depressant effects on behavior. Further, alcohol effect is also known to depend on strain-linked characteristics and on emotional ground of animals. Since prolonged isolation may differently change the emotional setting of mice, according to the strain, the behavioral effects of alcohol on avoidance learning, have been studied in two strains of male mice differentially housed. Evidences were obtained that ethanol çan either improve or worsen learning performances according to the strain and the housing conditions adopted.
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