Iranian Biomedical Journal
Volume:18 Issue: 3, Jul 2014

Polyphenols have been shown to have some of the neuroprotective effects against neurodegenerative diseases. These effects are attributed to a variety of biological activities، including free radical scavenging/antioxidant and anti-inflammatory and anti-apoptotic activities. In this regard، many efforts have been made to study the effects of various well-known dietary polyphenols on spinal cord injury (SCI) and to explore the mechanisms behind the neuroprotective effects. The aim of this paper is to present the mechanisms of neuroprotection of natural polyphenols used in animal models of SCI.

Cholera toxin B subunit (CTB) has been extensively considered as an immunogenic and adjuvant protein, but its yield of expression is not satisfactory in many studies. The aim of this study was to compare the expression of native and mutant recombinant CTB (rCTB) in pQE vector. ctxB fragment from Vibrio cholerae O1 ATCC14035 containing the substitution of mutant ctxB for amino acid S128T was amplified by PCR and cloned in pGETM-T easy vector. It was then transformed to E. coli Top 10F' and cultured on LB agar plate containing ampicillin. Sequence analysis confirmed the mature ctxB gene sequence and the mutant one in both constructs which were further subcloned to pQE-30 vector. Both constructs were subsequently transformed to E. coli M15 (pREP4) for expression of mature and mutant rCTB. SDS-PAGE analysis showed the maximum expression of rCTB in both systems at 5 hours after induction and Western-blot analysis confirmed the presence of rCTB in blotting membranes. The expression of mutant rCTB was much higher than mature rCTB, which may be the result of serine-to-threonine substitution at position 128 of mature rCTB amino acid sequence created by PCR mutagenesis. The mutant rCTB retained pentameric stability and its ability to bind to anti- cholera toxin IgG antibodies. Point mutation in ctxB sequence resulted in over-expression of rCTB, probably due to the increase of solubility of produced rCTB. Consequently, this expression system can be used to produce rCTB in high yield.

The seladin-1 (selective Alzheimer disease indicator-1)، also known as DHCR24، is a gene found to be down-regulated in brain region affected by Alzheimer disease (AD). Whereas، hair follicle stem cells (HFSC)، which are affected in with neurogenic potential، it might to hypothesize that this multipotent cell compartment is the predominant source of seladin-1. Our aim was to evaluate seladin-1 gene expression in hair follicle stem cells. In this study، bulge area of male Wistar rat HFSC were cultured and then characterized with Seladin-1 immunocytochemistry and flow cytometry on days 8 to 14. Next، 9-11-day cells were evaluated for seladin-1 gene expression by real-time PCR. Our results indicated that expression of the seladin-1 gene (DHCR24) on days 9، 10، and 11 may contribute to the development of HFSC. However، the expression of this gene on day 11 was more than day 10 and on 10th day was more than day 9. Also، we assessed HFSC on day 14 and demonstrated these cells were positive for β-ш tubulin، and seladin-1 was not expressed in this day. HFSC express seladin-1 and this result demonstrates that these cells might be used to cell therapy for AD in future.

Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common genetic kidney disorders with the incidence of 1 in 1،000 births. ADPKD is genetically heterogeneous with two genes identified: PKD1 (16p13. 3، 46 exons) and PKD2 (4q21، 15 exons). Eighty five percent of the patients with ADPKD have at least one mutation in the PKD1 gene. Genetic studies have demonstrated an important allelic variability among patients، but very few data are known about the genetic variation among Iranian populations. In this study، exon direct sequencing of PKD1 was performed in a seven-year old boy with ADPKD and in his parents. The patient’s father was ADPKD who was affected without any kidney dysfunction، and the patient’s mother was congenitally missing one kidney. Molecular genetic testing found a mutation in all three members of this family. It was a missense mutation GTG>ATG at position 3057 in exon 25 of PKD1. On the other hand، two novel missense mutations were reported just in the 7-year-old boy: ACA>GCA found in exon 15 at codon 2241 and CAC>AAC found in exon 38 at codon 3710. For checking the pathogenicity of these mutations، exons 15، 25، and 38 of 50 unrelated normal cases were sequenced. our findings suggested that GTG>ATG is a polymorphism with high frequency (60%) as well as ACA>GCA and CAC>AAC are polymorphisms with frequencies of 14% and 22%، respectively in the population of Southwest Iran.

The cultured mesenchymal stem cells (MSC) have been used in many clinical trials; however، there are still some concerns about the cultural conditions. One concern is related to the use of FBS as a widely used xenogeneic supplement in the culture system. Human platelet-rich plasma (hPRP) is a candidate replacement for FBS. In this study، the effect of hPRP on MSC proliferation and osteogenic differentiation has been evaluated.

Human adipose-derived stem cells (hADSC) were expanded. Cells from the third passage were characterized by flow cytometric analysis and used for in vitro experiments. Resazurin and alizarin red stains were used for cell proliferation and osteogenic differentiation assays، respectively.

Treatment with hPRP resulted in a statistically significant increase in cell proliferation compare to the negative control group (P<0. 001). Cell proliferation in the 15% hPRP group was also significantly higher than that in the 10% hPRP group (P<0. 05). Additionally، it caused less osteogenic differentiation of the hADSC compared to the FBS (P<0. 001)، but in comparison to negative control، it caused acceptable mineralization (P<0. 001).

These findings indicate that hPRP not only improves the proliferation but also it can be a suitable substitution in osteogenic differentiation for clinical purposes. However، the clinical application value of hPRP still needs more investigation.

The aim of this study was to determine the prevalence of virulence-associated genes and enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) analysis of Campylobacter spp. isolated from children with diarrhea in Iran. A total of 200 stool specimens were obtained from children under 5 years during July 2012 to July 2013. Detection of C. jejuni and C. coli was performed by standard biochemical and molecular methods. The presence of virulence-associated genes and genetic diversity of isolates was examined using PCR and ERIC-PCR analyses. A total of 12 (6%) Campylobacter spp. were isolated from patients including 10 (4. 5%) C. jejuni and 2 (1. 5%) C. coli. The flaA، cadF and ciaB genes were present in 100% of isolates، while no plasmid of virB11 gene was present in their genome. The prevalence of invasion-associated marker was 100% among C. coli and was not detected in C. jejuni isolates. The distribution of both pldA and the genes associated with cytolethal distending toxin (CDT) was 58. 3% in C. jejuni isolates. Seven distinct ERIC-PCR profiles were distinguished in three clusters using ERIC-PCR analysis. Genotyping analysis showed a relative correlation with geographic location of patients and virulence gene content of isolates. To our knowledge، this is the first molecular survey of Campylobacter spp. in Iran concerning genotyping and virulence gene content of both C. jejuni and C. coli. ERIC-PCR revealed appropriate discriminatory power for clustering C. jejuni isolates with identical virulence gene content. However، more studies are needed to clearly understand the pathogenesis properties of specific genotypes.

Defects in endoplasmic reticulum homeostasis are common occurrences in different diseases، such as diabetes، in which the function of endoplasmic reticulum is disrupted. It is now well established that ion channels of endoplasmic reticulum membrane have a critical role in endoplasmic reticulum luminal homeostasis. Our previous studies showed the presence of an ATP-sensitive cationic channel in endoplasmic reticulum. Therefore، in this study، we examined and compared the activities of this channel in control and diabetic rats using single-channel recording techniques. Male Wistar rats were made diabetic for 2 weeks with a single dose injection of streptozotocin (45 mg/kg). Ion channel incorporation of rough endoplasmic reticulum of diabetic hepatocytes into the bilayer lipid membrane allowed the characterization of K+ channel. Ion channel incorporation of rough endoplasmic reticulum vesicles into the bilayer lipid revealed that the channel current-voltage (I-V) relation with a mean slope conductance of 520 ± 19 pS was unaffected in diabetes. Interestingly، the channel Po-voltage relation was significantly lower in diabetic rats at voltages above +30 mV. We concluded that the endoplasmic reticulum cationic channel is involved in diabetes. Also، this finding could be considered as a goal for further therapeutic plans.

Data shows vanadium protects pancreatic beta cells (BC) from diabetic animals. Whether this effect is direct or through the relief of glucose toxicity is not clear. This study evaluated the potential effect of oral vanadyl sulfate (vanadium) on glycemic status and pancreatic BC of normal and diabetic rats. Rats were divided into five groups of normal and diabetic. Diabetes was induced with streptozocin (40 mg/kg، i. v.). Normal rats used water (CN) or vanadium (1 mg/ml VOSO4، VTN). Diabetic rats used water (CD)، water plus daily neutral protamine Hagedorn insulin injection (80 U/kg، ITD) or vanadium (VTD). Blood samples were taken for blood glucose (BG، mg/dL) and insulin (ng/dL) measurements. After two months، the pancreata of sacrificed rats were prepared for islet staining. Pre-treated normal BG was 88 ± 2، and diabetic BG was 395 ± 9. The final BG in CD، VTD، and ITD was 509 ± 22، 138 ± 14، and 141 ± 14، respectively. Insulin in VTN (0. 75 ± 0. 01) and VTD (0. 78 ± 0. 01) was similar، higher than CD (0. 51 ± 0. 07) but lower than CN (2. 51 ± 0. 02). VTN islets compared to CN had larger size and denser central core insulin immunoreactivity with plentiful BC. CD and ITD islets were atrophied and had scattered insulin immunoreactivity spots and low BC mass. VTD islets were almost similar to CN. Besides insulin-like activity، vanadium protected pancreatic islet BC، and the relief of glucose toxicity happening with vanadium had a little role in this action.

Cryopreservation of pre-antral follicles is a hopeful technique to preserve female fertility. The aim of the present study was to evaluate reactive oxygen species (ROS) and total antioxidant capacity (TAC) levels of mouse vitrified pre-antral follicles in the presence of alpha lipoic acid (ALA). Isolated pre-antral follicles (140–150 µm in diameter) were divided into vitrified–warmed and fresh groups. Each group was subjected to in vitro maturation with or without ALA for 12 days، followed by adding human chronic gonadotropin to induce ovulation. In vitro fertilization was performed to evaluate their developmental competence. In parallel، the amount of ROS and TAC were assessed after 0، 24، 48، 72، and 96 h of culture by 2''،7''-dichlorofluorescin assay and ferric reducing/antioxidant power assay، respectively. The respective rates of survival، antrum formation، and metaphase II oocytes were significantly higher in ALA-supplemented groups compared to the groups not treated with ALA. TAC and ROS levels were significantly decreased and increased، respectively during the culture period up to 96 h in the absence of ALA in both vitrified and non-vitrified samples. However، with pretreatment of ALA، TAC levels were increased significantly and remained constant up to 96 h in vitrified-warmed pre-antral follicles، while ROS levels completely returned to the level of starting point after 96 h of culture in the presence of ALA. Pretreatment of ALA positively influences development of pre-antral follicles in vitrified and non-vitrified samples through increasing follicular TAC level and decreasing ROS levels.

Pasteur Institute of Iran was established in 1919 with the aim to produce vaccines and prevent communicable diseases in Iran. Over time، their activities extended into areas of research، education and services. Naturally، such a vast development begs establishment of a comprehensive management and monitoring system. With this outlook، the present study was carried out with the aim to design a performance assessment model for Pasteur Institute of Iran that، in addition to determining evaluation indicators، it could prepare the necessary grounds for providing a unified assessment model for the global network of the Pasteur Institutes. This study was designed and performed in 4 stages: first; design of indicators and determining their scores. Second; editing indicators according to the outcome of discussions and debates held with members of Research Council of Pasteur Institute of Iran. Third; implementation of a pilot model based on the Institute’s activities in 2011. Fourth; providing the pilot model feedback to the stakeholders and finalizing the model according to an opinion survey. Based on the results obtained، the developed indicators for Pasteur Institute of Iran evaluation were designed in 10 axes and 18 sub-axes، which included 101 major and 58 minor indicators. The axes included governance and leadership، resources and facilities، capacity building، knowledge production and collaborations، reference services، economic value of products and services، participation in industrial exhibitions، status of the institute، satisfaction and institute’s role in health promotion. The indicators presented in this article have been prepared based on the balance in the Institute’s four missions، to provide the basis for assessment of the Institute’s activities in consecutive years، and possibility of comparison with other institutes worldwide.