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1.  Nicotinamide-functionalized multiwalled carbon nanotubes increase insulin production in pancreatic beta cells via MIF pathway 
Recent data in the literature support the role of nicotinamide (NA) as a pharmacologic agent that stimulates pancreatic beta-cells to produce insulin in vitro. There are data showing that carbon nanotubes may be useful in initiating and maintaining cellular metabolic responses. This study shows that administration of multiwalled carbon nanotubes (MWCNTs) functionalized with nicotinamide (NA-MWCNTs) leads to significant insulin production compared with individual administration of NA, MWCNTs, and a control solution. Treatment of 1.4E7 cells for 30 minutes with NA-MWCNTs at concentrations ranging from 1 mg/L to 20 mg/L resulted in significantly increased insulin release (0.18 ± 0.026 ng/mL for 1 mg/L, 0.21 ± 0.024 ng/mL for 5 mg/L, and 0.27 ± 0.028 ng/mL for 20 mg/L). Thus, compared with cells treated with NA only (0.1 ± 0.01 ng/mL for 1 mg/L, 0.12 ± 0.017 ng/mL for 5 mg/L, and 0.17 ± 0.01 ng/mL for 20 mg/L) we observed a significant positive effect on insulin release in cells treated with NA-MWCNTs. The results were confirmed using flow cytometry, epifluorescence microscopy combined with immunochemistry staining, and enzyme-linked immunosorbent assay techniques. In addition, using immunofluorescence microscopy techniques, we were able to demonstrate that MWCNTs enhance insulin production via the macrophage migration inhibitory factor pathway. The application and potential of NA combined with MWCNTs as an antidiabetic agent may represent the beginning of a new chapter in the nanomediated treatment of diabetes mellitus.
PMCID: PMC3770514  PMID: 24039418
carbon nanotubes; NA; insulin-producing cells; insulin; macrophage migration inhibitory factor; diabetes mellitus
2.  Ethinylestradiol30μg-drospirenone and metformin: could this combination improve endothelial dysfunction in polycystic ovary syndrome? 
We are hereby investigating for the first time the effect of the association ethinylestradiol30μg-drospirenone 3mg (DRP/EE30μg) plus metformin and weight loss on endothelial status and C-reactive protein (hsCRP) levels in polycystic ovary syndrome (PCOS).
25 young women with PCOS (mean age 22.76 ± 0.83 years, body mass index (BMI): 28.44 ± 6.23) who completed the study were prospectively evaluated. The oral contraceptive- DRP/EE30μg (21 days/month) and metformin (1700 mg daily) were administered for 6 months to the PCOS group. Additionally, the 15 overweight and obese patients (BMI > 25 kg/m2) were instructed in a diet of no more than 1500 cal daily. Primary outcome measures were surrogate markers of cardiovascular disease and included endothelial function, i.e. flow-mediated dilatation (FMD) on the brachial artery and endothelin-1 levels, as well as hsCRP concentrations, body composition (measured by whole-body dual-energy X-ray-absorptiometry) and insulin resistance. Variables were assessed at baseline, as well as after our medical intervention.
The combination between DRP/EE30μg plus metformin combined with weight loss triggered a significant improvement in the FMD values (FMD-PCOSbasal 3.48 ± 1.00 vs FMD-PCOS6 months7.43 ± 1.04, p = 0.033), as well as body composition and insulin insensitivity (p < 0.05). Regarding hsCRP levels, there was no significant intragroup (PCOS6months – PCOSbasal) difference.
A 6-month course of metformin- DRP/EE30μg (associated with weight loss) improves the endothelial dysfunction in PCOS and shows neutral effects on hsCRP concentrations as an inflammation marker. These data demand for reevaluation of the medical therapy in PCOS, particularly in women with additional metabolic and cardiovascular risk factors ( Identifier: NCT01459445).
PMCID: PMC3413550  PMID: 22713099
Ethinylestradiol30μg-drospirenone; Flow-mediated dilatation; Endothelial dysfunction; HsCRP; Metformin; Polycystic ovary syndrome
3.  Influence of nanomaterials on stem cell differentiation: designing an appropriate nanobiointerface 
During the last decade, due to advances in functionalization chemistry, novel nanobiomaterials with applications in tissue engineering and regenerative medicine have been developed. These novel materials with their unique physical and chemical properties are bioactive hierarchical structures that hold great promise for future development of human tissues. Thus, various nanomaterials are currently being intensively explored in the directed differentiation of stem cells, the design of novel bioactive scaffolds, and new research avenues towards tissue regeneration. This paper illustrates the latest achievements in the applications of nanotechnology in tissue engineering in the field of regenerative medicine.
PMCID: PMC3356220  PMID: 22619557
nanotechnology; nanomaterials; tissue engineering; regeneration; stem cell differentiation

Results 1-3 (3)