BackgroundRepaglinide is an efficient anti-diabetic drug which is prescribed widely as multi-dosage oral daily regimens. Due to the low compliance inherent to each multi-dosage regimen, development of prolonged-release formulations could enhance the overall drug efficacy in patient populations.MethodsRepaglinide-loaded solid lipid nanoparticles (SLNs) were developed and characterized in vitro. Various surfactants were used in this study during the nanocarrier preparation procedure and their corresponding effects on some physicochemical properties of SLNs such as size, zeta potential; drug loading parameters and drug release profiles was investigated. Stearic acid and glyceryl mono stearate (GMS) were used as lipid phase and phosphatidylcholin, Tween80, Pluronic F127, poly vinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) were used as surfactant/stabilizer.ResultsThe results showed some variations between formulations; where the Tween80-based SLNs showed smallest size, the phosphatidylcholin-based SLNs indicated most prolonged drug release time and the highest loading capacity. SEM images of these formulations showed morphological variations and also confirmed the nanoscale size of these particles. The FTIR and DSC results demonstrated no interaction between drug and excipients. The invitro release profiles of different formulations were studied and observed slow release of drug from all formulations. However significant differences were found among them in terms of their initial burst release as well as the whole drug release profile. From fitting these data to various statistical models, the Peppas model was proposed as the best model to describe the statistical indices and, therefore, mechanism of drug release.ConclusionThe results of this study confirmed the effect of surfactant type on SLNs physicochemical properties such as morphological features, loading parameters, particle sizes and drug release kinetic. With respect to the outcome data, the mixture of phosphatidylcholin/Pluronic F127 was selected as the best surfactant/stabilizer to coat the lipid core comprising stearic acid and GMS.

The regulatory T (Treg) cells play a major role in the control of the autoimmunity and inflammation, and IL-35 has been described as an immunosuppressive cytokine that is mainly produced by CD4(+)FOXP3(+) Treg cells. The aim of this study was to evaluate the serum levels of IL-35 and a single nucleotide polymorphism (SNP), rs3761548, in FOXP3 gene in patients with multiple sclerosis. The blood samples were collected from 140 multiple sclerosis (MS) patients (including 51 untreated and 89 treated patients) and 140 healthy subjects as a control group. The serum levels of IL-35 were measured by ELISA. The DNA was analyzed for SNP rs3761548 in FOXP3 gene using SSP-PCR. There was no significant difference between untreated MS patients and control group regarding the mean serum levels of IL-35, although this parameter was higher in untreated patients. However, the mean serum level of IL-35 in treated MS patients was significantly higher than that in the control group (P < 0.008). The mean serum levels of IL-35 in patients who were treated with interferon-β, methylprednisolone, or with the both interferon-β and methylprednisolone were significantly higher than that in the healthy group (P < 0.01, P < 0.01, and P < 0.2, respectively). The frequencies of AA and AC genotypes at rs3761548 in the FOXP3 gene were significantly higher in MS group as compared with healthy subjects (P < 0.05). The frequency of CC genotype at rs3761548 was significantly lower in the MS group in comparison with healthy control subjects (P < 0.001). Moreover, the frequency of A allele was significantly higher whereas the frequency of C allele was significantly lower in MS patients in comparison to healthy subjects (P < 0.001). The mean serum level of IL-35 was significantly lower in MS patients or healthy subjects with AA genotype as compared with those with CC genotype at rs3761548 in FOXP3 gene (P < 0.01 and P < 0.001, respectively). These results showed higher serum levels of IL-35 in treated MS patients representing that the benefit effects of treatment may in part performed through the upregulation of the IL-35 production. The SNP rs3761548 may influence the susceptibility to MS disease and the serum levels of IL-35.

The imbalance in Th17/Treg cell-related responses plays an important role in the pathogenesis of multiple sclerosis (MS). The development of Th17- and Treg cells is regulated by specific transcription factors-RORγt and RORα-and FOXP3, respectively. The aim was to determine the expression of RORγt, RORα, and FOXP3 in peripheral blood mononuclear cells (PBMCs) from MS patients following in vitro stimulation. The PBMCs from 22 MS patients and 20 healthy subjects were cultured in the presence of 10 μg/ml MOG, 10 μg/ml PHA, or without stimulation. The PBMCs were incubated at 37 °C for 24 h, and then the messenger RNA (mRNA) expression of RORγt, RORα, and FOXP3 was determined by real-time PCR. The expression of RORγt and RORα was increased in non-stimulated, MOG-stimulated, and PHA-stimulated PBMCs from MS patients in comparison with same cultures from the healthy group (P < 0.01, P < 0.01, and P < 0.02 for RORγt; P < 0.001, P < 0.001, and P < 0.05, for RORα, respectively). The FOXP3 expression in non-stimulated PBMCs from MS patients was significantly lower than that in equal culture from healthy subjects (P < 0.05). There were no significant differences between healthy subjects and MS patients regarding the expression of FOXP3 mRNA by MOG-stimulated and PHA-stimulated PBMCs. These results showed an imbalance in Th17/Treg cells at transcription factor levels with a deviation toward Th17 cell in MS. The correction of Th17/Treg balance at transcription levels should be considered to design novel therapeutic strategies for MS treatment.

Our results showed increased concentrations of IL-33 in patients with MS including both untreated and treated MS patients and patients with the RRMS, SPMS, and PPMS forms. This suggests that IL-33 may be involved in the pathogenesis of all MS forms and treatment with methylprednisolone or both interferon-β plus methylprednisolone has no influence on IL-33 concentrations.

Chemokines play an important role in the autoimmune diseases. The aim of this study was to investigate the levels of CCL20 and a polymorphism [-786C > T (rs6749704)] in the chemokine gene in patients with multiple sclerosis (MS). The blood samples were collected from 135 MS patients and 135 healthy subjects as a control group. The patients have relapsing-remitting (RRMS; n = 65), primary progressive (PPMS; n = 47), secondary progressive (SPMS; n = 35) or progressive relapsing (PRMS; n = 14) patterns. The serum levels of CCL20 were measured by ELISA. The DNA was analyzed for CCL20 polymorphism using PCR-RLFP. The mean serum levels of CCL20 in the MS group were significantly higher than in the healthy group (P < 0.001). In patients with a SPMS pattern, the frequency of CT genotype at rs6749704 (24.3 %) was significantly lower as compared to patients with other patterns (42.8 %; P < 0.04). No significant differences were observed between subjects with different genotypes in rs6749704 regarding the CCL20 levels. The mean serum levels of CCL20 in both newly diagnosed and previously diagnosed patients was significantly higher than in the healthy group (P < 0.05 and 0.001, respectively). The mean serum levels of CCL20 in patients with RRMS, SPMS and PPMS patterns were significantly higher than in the healthy group (P < 0.004, P < 0.04, and 0.05, respectively). The levels of CCL20 in untreated patients and in patients who received interferon-β, methylprednisolone or the combination of interferon-β plus methylprednisolone were higher as compared to the control group (P < 0.05, P < 0.03, P < 0.005, and P < 0.05, respectively). These results showed higher levels of CCL20 in patients that represent that the chemokine may play an important role in the pathogenesis of MS. The rs6749704 polymorphism was an associated SPMS pattern. The levels of CCL20 were not influenced by gender, disease pattern and treatment.

Chemokines play a major role in autoimmune diseases such as multiple sclerosis (MS). Gender also affects the susceptibility and course of MS. The aim of this study was to investigate the serum levels of the macrophage-derived chemokine (CCL22) in women and men patients with MS. Blood samples were collected from 135 healthy subjects (35 men and 100 women) and 135 MS patients (29 men and 136 women; 47 newly diagnosed and 88 treated patients and have relapsing-remitting (RRMS; n = 65), secondary progressive (SPMS; n = 37), primary progressive (PPMS; n = 19), or progressive relapsing (PRMS; n = 14) patterns). The serum levels of CCL22 were measured by ELISA. The difference of the mean serum levels of CCL22 between the newly diagnosed MS men and healthy men was not significant, but in newly diagnosed MS women, the mean serum levels of CCL22 were significantly lower than those in treated MS women and healthy women (P < 0.006 and P < 0.0001, respectively). The differences of the mean CCL22 levels between men patients with different treatment programs were not significant, but the mean CCL22 levels were significantly higher in women treated with interferon-β or the combination of interferon-β plus methylprednisolone as compared to untreated women patients (P < 0.01 and P < 0.05, respectively). The CCL22 levels were also significantly higher in women with RRMS and PRMS patterns in comparison to healthy women (P < 0.05 and P < 0.01, respectively). These results showed lower levels of CCL22 in women patients which represents that the reduction in CCL22 levels may play an important role in the pathogenesis of the disease in women. In women patients, the levels of CCL22 were influenced by disease pattern and treatment.

No abstract

Vitamin D deficiency/insufficiency is currently considered to be a re-emerging public health problem globally. This study was designed to determine the prevalence of vitamin D deficiency and insufficiency and to investigate its trend from 2001 to 2013 in a longitudinal study of Iranian adults. This study was part of a population-based, longitudinal ongoing study of Iranian healthy adults aged 35 y and older at baseline. Serum vitamin D level was assessed in a sub-sample of 370 subjects, who were apparently healthy at the time of recruitment in 2001 and were free from MetS, in three phases (2001, 2007 and 2013) during the 12-y study period. Adjusted prevalence and trend of vitamin D deficiency were calculated. Mean serum vitamin D levels increased over the time of the study (52.12, 54.27 and 62.28 nmol/L, respectively) and the prevalence of vitamin D deficiency decreased (30.5, 27.0 and 24.4, respectively). However, the prevalence of vitamin D insufficiency did not change over this time period. The risk of vitamin D deficiency decreased significantly in 2007 [OR: 0.73 (95% CI: 0.53, 0.99)] and 2013 [OR: 0.50 (95% CI: 0.36, 0.70)] compared to the baseline. The present study demonstrated some improvement in serum vitamin D levels, while the prevalence of vitamin D inadequacy was still high. Considering the possible health consequences of vitamin D deficiency, there is an urgent need for developing population-wide strategies, such as supplementation and fortification, to prevent or control vitamin D deficiency. Key Words vitamin D deficiency, vitamin D insufficiency, prevalence, longitudinal study Vitamin D deficiency was identified as a public health problem more than two hundred years ago, during the Industrial Revolution (1). The problem declined as a result of the discovery of vitamin D and increased intake of vitamin D. However, as a consequence of modern lifestyles, more indoor activities and the inadequate amount of vitamin D in most people's diets (2), the number of individuals with low serum 25-hydroxyvita-min D (25(OH)D) levels has been increasing (3). Vitamin D has long been recognized for its role in the regulation of calcium and phosphorus homeostasis and bone health (4). Moreover, there is also an increasing body of evidence that has found an association between vitamin D deficiency and other health problems (5). For example, the risk of all-cause and cardiovascular mortality was reported higher in people with a lower level of serum 25(OH)D (6-8). Although the optimal serum level of 25(OH)D in humans is not fully recognised, several expert groups have considered levels of less than 25 nmol/L to be a 'deficiency' and 25-50 nmol/L to be an 'insufficiency' (9, 10). Due to the potential health problems related to vitamin D deficiency and its increasing prevalence, vitamin D deficiency/insufficiency is currently recognized as a re-emerging public health problem at the global level (11). It is estimated that more than one billion people are vitamin D deficient/insufficient (12). For example, the prevalence o...