mehrdad bakhtiari - Academia.edu (original) (raw)

Papers by mehrdad bakhtiari

Research paper thumbnail of Alpha-1 antitrypsin, retinol binding protein and keratin 10 alterations in patients with psoriasis vulgaris, a proteomic approach

Iranian Journal of Basic Medical Sciences, 2014

Objective(s): Psoriasis is an autoimmune disease that appears on the skin. Although psoriasis is ... more Objective(s): Psoriasis is an autoimmune disease that appears on the skin. Although psoriasis is clinically and histologically well characterized, its pathogenesis is unknown in detail. The aims of this study were to evaluate the proteome of psoriatic patients' sera and to compare them with those of normal healthy human to find valuable biomarkers. Materials and Methods: In a case-control study, twenty cases of white patients with psoriasis vulgaris, 10 males and 10 females and sixteen healthy controls, 8 males and 8 females were enrolled in the study. The serum protein expression patterns obtained after depletion of albumin were compared by using two dimensional gel electrophoresis (2-DE) coupled to MALDI/TOF-TOF to identify disease associated proteins. Results: Differential expression of nine protein spots representing four unique proteins including alpha-1 antitrypsin, retinol binding protein, keratin 10 and an unknown protein (with pI 6.47 and molecular weight of 19941 Da), ...

Research paper thumbnail of Fine-mapping the Favored Mutation in a Positive Selective Sweep

Methods to identify signatures of selective sweeps in population genomics data have been actively... more Methods to identify signatures of selective sweeps in population genomics data have been actively developed, but mostly do not identify the specific mutation favored by the selective sweep. We present a method, iSAFE, that uses a statistic derived solely from population genetics signals to pinpoint the favored mutation even when the signature of selection extends to 5Mbp. iSAFE was tested extensively on simulated data and in human populations from the 1000 Genomes Project, at 22 loci with previously characterized selective sweeps. For 14 of the 22 loci, iSAFE ranked the previously characterized candidate mutation among the 13 highest scoring (out of ∼ 21, 000 variants). Three loci did not show a strong signal. For the remaining loci, iSAFE identified previously unreported mutations as being favored. In these regions, all of which involve pigmentation related genes, iSAFE identified identical selected mutations in multiple non-African populations suggesting an out-of-Africa onset of ...

Research paper thumbnail of Correction to: Transplantation of Human Chorion-Derived Cholinergic Progenitor Cells: a Novel Treatment for Neurological Disorders

Molecular neurobiology, Jan 26, 2018

The original version of this article unfortunately contained mistake in the affiliation. Affiliat... more The original version of this article unfortunately contained mistake in the affiliation. Affiliation 1 should be read as "Neuroscience Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran". The original article has been corrected.

Research paper thumbnail of Identifying the favored mutation in a positive selective sweep

Nature methods, 2018

Most approaches that capture signatures of selective sweeps in population genomics data do not id... more Most approaches that capture signatures of selective sweeps in population genomics data do not identify the specific mutation favored by selection. We present iSAFE (for "integrated selection of allele favored by evolution"), a method that enables researchers to accurately pinpoint the favored mutation in a large region (∼5 Mbp) by using a statistic derived solely from population genetics signals. iSAFE does not require knowledge of demography, the phenotype under selection, or functional annotations of mutations.

Research paper thumbnail of Purity determining of cultured OECs from olfactory mucosa of rats\' pups

Journal of Basic Research in Medical Sciences

Introduction: Cell transplantation is one of the main strategies for spinal cord injury repair. A... more Introduction: Cell transplantation is one of the main strategies for spinal cord injury repair. As OECs of the olfactory mucosa can be obtained by simple biopsy in all individuals without affecting their smell sensation, OECs considered as a promising candidate for autologous transplantation in the nervous system injury, especially for spinal cord repair. Thereby in the current study OECs were cultured from olfactory mucosa of 7 days old rats' pups and their purity was examined by flow-cytometry after simultaneous double staining for p75 and GFAP markers. Materials and methods: 7 days old Wistar rats' pups were deeply anesthetized by ketamine / xylazine (60/6mg/Kg). Then the nasal cavity was opened sagittally and the olfactory mucosa was separated from posterior part of nasal septum and at last OECs were obtained from lamina properia of olfactory mucosa and were cultured. The cultured cells were simultaneously immunolabeled for p75 and GFAP markers and finally purity of cultured cells assessed by flow-cytometry. Results: cultured OECs demonstrated two different morphologies, a spindle shape Schwannlike and an astrocyte-like OECs with flat sheet-like morphology. In addition, simultaneous immunolabeling for p75 and GFAP markers of OECs exhibited OECs were positive for both markers at the same time. The flow-cytometry results displayed that 87.9±2.4% of cells were p75/ GFAP double positive cells,1.05±0.4 only p75 positive and 5.8±1.5% were single positive for GFAP. Conclusion: Purity of cultured OECs in our study is probably more than 87.9% by flowowing to p75+/S100+ and GFAP+/S100+ olfactory ensheathing cells were not counted. Thus the culture procedure of this study seems to be a good protocol for OECs purifying and cell therapy in CNS damages.

Research paper thumbnail of The combined application of human adipose derived stem cells and Chondroitinase ABC in treatment of a spinal cord injury model

Neuropeptides, 2016

Although stem cell therapy has become a major focus as a new option for management of spinal cord... more Although stem cell therapy has become a major focus as a new option for management of spinal cord injury (SCI), its effectiveness should be promoted. In this study, we investigated the effects of co-administrating human adipose-derived stem cells (hADSCs) and Chondroitinase ABC (ChABC) in a rat model of spinal cord injury. hADSCs derived from superficial layer of abdominal adipose tissue were used to treat a contusion-induced SCI. Animals were randomly allocated to five equal groups including sham (only laminectomy), SCI (SCI+vehicle injection), hADSCs (1×10⁶ hADSCs/10μl intra-spinal injection), ChABC (10μl of 100U/ml ChABC intra-spinal injection injection), and hADSCs+ChABC. Basso, Beattie and Bresnahan tests were used to evaluate locomotor function. 8weeks after treatment, cavity size, myelination, cell differentiation (neuron and astrocyte), and chondroitin sulfate amount were analyzed. hADSC transplanted animals, ChABC injected animals (P<0.001), and hADSC+ChABC treated rats (P<0.001) displayed significant motor improvement compared to SCI group. Combination therapy of hADSCs and ChABC led to greater locomotor recovery compared to using hADSCs (P<0.001) or ChABC (P<0.01) alone. Spinal cords in the combined and single therapy groups had cavities filled with myelinated areas and less chondroitin sulfate content in comparison with the control group (P<0.001). hADSCs expressed GFAP, B III tubulin and Map2. Combination therapy with ChABC and hADSCs exhibits more significant functional recovery than single therapy using either. This result may be applicable in selection of the best therapeutic strategy for SCI.

Research paper thumbnail of Study of the effect of exogenous melatonin on sperm fertility in busulfan induced oligospermic of pinealectomeized rat

Razi Journal of Medical Sciences, Aug 15, 2013

Research paper thumbnail of The role of biodegradable engineered nanofiber scaffolds seeded with hair follicle stem cells for tissue engineering

Iranian biomedical journal, 2012

The aim of this study was to fabricate the poly caprolactone (PCL) aligned nanofiber scaffold and... more The aim of this study was to fabricate the poly caprolactone (PCL) aligned nanofiber scaffold and to evaluate the survival, adhesion, proliferation, and differentiation of rat hair follicle stem cells (HFSC) in the graft material using electrospun PCL nanofiber scaffold for tissue engineering applications. The bulge region of rat whisker was isolated and cultured in DMEM: nutrient mixture F-12 supplemented with epidermal growth factor. The morphological and biological features of cultured bulge cells were observed by light microscopy using immunocytochemistry methods. Electrospinning was used for production of PCL nanofiber scaffolds. Scanning electron microscopy (SEM), 3-(4, 5-di-methylthiazol- 2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, and histology analysis were used to investigate the cell morphology, viability, attachment and infiltration of the HFSC on the PCL nanofiber scaffolds. The results of the MTT assay showed cell viability and cell proliferation of the HFSC on...

Research paper thumbnail of Optimization of nose shape of Launch Vehicle using genetic algorithm and response surface methods

2009 4th International Conference on Recent Advances in Space Technologies, 2009

In this study, to reduce the drag force, the nose shape of Launch Vehicle with determined flight ... more In this study, to reduce the drag force, the nose shape of Launch Vehicle with determined flight conditions, is optimized. Two optimization methods are considered: binary genetic algorithm and response surface method. Since the value of drag coefficient is proportional to dynamic pressure, the objective function is based on minimization of drag coefficient in flight conditions which is corresponding to

Research paper thumbnail of Comparison of Human Adipose-Derived Stem Cells and Bone Marrow-Derived Stem Cells in a Myocardial Infarction Model

Cell Transplantation, 2014

Spinal cord injury (SCI) is one of the most serious clinical diseases and its treatment has been ... more Spinal cord injury (SCI) is one of the most serious clinical diseases and its treatment has been a subject of interest to researchers. There are two important therapeutic strategies in the treatment of SCI: replacing lost tissue cells through cells implantation and scar elimination. Therefore, in this study we used human adipose-derived stem cells (hADSCs) implantation and injection of Chondroitinase ABC. Aim of present study was to answer to this question: which one is more efficient for Improvement of locomotor recovery after SCI in rat? Transplantation of hADSCs or injection of ChABC. The spinal cord of rats was injured by contusion using a weight-drop at the level of T8-9, the hADSCs and Chondroitinase ABC were infused in to the spinal cord tissue after injury. BBB test was performed and recorded for each animal weekly for 8 weeks. After the 8(th) weeks, Serial cross-sections were stained with cresyl violet and examined under a light microscope and area of cavity in the spinal cord was measured. At 8(th) weeks after injection, hADSCs and ChABC significantly promote locomotor function (P<0.01) and spinal cords of hADSCs and ChABC group had cavities much smaller than those of the control group (P<0.001). Results of the present study shows dealing with inappropriate neuro-inhibitory environment and glial scar by ChABC have equal role compare to cell therapy (with hADSCs) for improving motor function after SCI and this result in adoption of proper therapeutic strategies for SCI intervention is important.

Research paper thumbnail of Co-transplantation of bone marrow stromal cells with schwann cells evokes mechanical allodynia in the contusion model of spinal cord injury in rats

Several studies have shown that, although transplantation of neural stem cells into the contusion... more Several studies have shown that, although transplantation of neural stem cells into the contusion model of spinal cord injury (SCI) promotes locomotor function and improves functional recovery, it induces a painful response, Allodynia. Different studies indicate that bone marrow stromal cells (BMSCs) and Schwann cells (SCs) can improve locomotor recovery when transplanted into the injured rat spinal cord. Since these cells are commonly used in cell therapy, we investigated whether co-transplantation of these cells leads to the development of Allodynia. In this experimental research, the contusion model of SCI was induced by laminectomy at the T8-T9 level of the spinal cord in adult female wistar rats (n=40) weighting (250-300g) using the New York University Device. BMSCs and SCs were cultured and prelabeled with 5-bromo-2-deoxyuridine (BrdU) and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) respectively. The rats were divided into five groups of 8 including: a control group (laminectomy only), three experimental groups (BMSC, SC and Co-transplant) and a sham group. The experimental groups received BMSCs, SCs, and BMSCs and SCs respectively by intraspinal injection 7 days after injury and the sham group received serum only. Locomotion was assessed using Basso, Beattie and Bresnahan (BBB) test and Allodynia by the withdrawal threshold test using Von Frey Filaments at 1, 7, 14, 21, 28, 35, 42, 49 and 56 days after SCI. The statistical comparisons between groups were carried out by using repeated measures analysis of variances (ANOVA). Significant differences were observed in BBB scores in the Co- transplant group compared to the BMSC and SC groups (p< 0.05). There were also significant differences in the withdrawal threshold means between animals in the sham group and the BMSC, SC and the Co-transplant groups (p<0.05).BBB scores and withdrawal threshold means showed that co-transplation improved functioning but greater Allodynia compared to the other experimental groups. The present study has shown that, although transplantation of BMSCs, SCs and a combination of these cells into the injured rat spinal cord can improve functional recovery, it leads to the development of mechanical Allodynia. This finding indicates that strategies to reduce Allodynia in cell transplantation studies are required.

Research paper thumbnail of Co-transplantation of bone marrow stromal cells with schwann cells evokes mechanical allodynia in the contusion model of spinal cord injury in rats

Several studies have shown that, although transplantation of neural stem cells into the contusion... more Several studies have shown that, although transplantation of neural stem cells into the contusion model of spinal cord injury (SCI) promotes locomotor function and improves functional recovery, it induces a painful response, Allodynia. Different studies indicate that bone marrow stromal cells (BMSCs) and Schwann cells (SCs) can improve locomotor recovery when transplanted into the injured rat spinal cord. Since these cells are commonly used in cell therapy, we investigated whether co-transplantation of these cells leads to the development of Allodynia. In this experimental research, the contusion model of SCI was induced by laminectomy at the T8-T9 level of the spinal cord in adult female wistar rats (n=40) weighting (250-300g) using the New York University Device. BMSCs and SCs were cultured and prelabeled with 5-bromo-2-deoxyuridine (BrdU) and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) respectively. The rats were divided into five groups of 8 including: a control group (laminectomy only), three experimental groups (BMSC, SC and Co-transplant) and a sham group. The experimental groups received BMSCs, SCs, and BMSCs and SCs respectively by intraspinal injection 7 days after injury and the sham group received serum only. Locomotion was assessed using Basso, Beattie and Bresnahan (BBB) test and Allodynia by the withdrawal threshold test using Von Frey Filaments at 1, 7, 14, 21, 28, 35, 42, 49 and 56 days after SCI. The statistical comparisons between groups were carried out by using repeated measures analysis of variances (ANOVA). Significant differences were observed in BBB scores in the Co- transplant group compared to the BMSC and SC groups (p< 0.05). There were also significant differences in the withdrawal threshold means between animals in the sham group and the BMSC, SC and the Co-transplant groups (p<0.05).BBB scores and withdrawal threshold means showed that co-transplation improved functioning but greater Allodynia compared to the other experimental groups. The present study has shown that, although transplantation of BMSCs, SCs and a combination of these cells into the injured rat spinal cord can improve functional recovery, it leads to the development of mechanical Allodynia. This finding indicates that strategies to reduce Allodynia in cell transplantation studies are required.

Research paper thumbnail of Alpha-1 antitrypsin, retinol binding protein and keratin 10 alterations in patients with psoriasis vulgaris, a proteomic approach

Iranian Journal of Basic Medical Sciences, 2014

Objective(s): Psoriasis is an autoimmune disease that appears on the skin. Although psoriasis is ... more Objective(s): Psoriasis is an autoimmune disease that appears on the skin. Although psoriasis is clinically and histologically well characterized, its pathogenesis is unknown in detail. The aims of this study were to evaluate the proteome of psoriatic patients' sera and to compare them with those of normal healthy human to find valuable biomarkers. Materials and Methods: In a case-control study, twenty cases of white patients with psoriasis vulgaris, 10 males and 10 females and sixteen healthy controls, 8 males and 8 females were enrolled in the study. The serum protein expression patterns obtained after depletion of albumin were compared by using two dimensional gel electrophoresis (2-DE) coupled to MALDI/TOF-TOF to identify disease associated proteins. Results: Differential expression of nine protein spots representing four unique proteins including alpha-1 antitrypsin, retinol binding protein, keratin 10 and an unknown protein (with pI 6.47 and molecular weight of 19941 Da), ...

Research paper thumbnail of Fine-mapping the Favored Mutation in a Positive Selective Sweep

Methods to identify signatures of selective sweeps in population genomics data have been actively... more Methods to identify signatures of selective sweeps in population genomics data have been actively developed, but mostly do not identify the specific mutation favored by the selective sweep. We present a method, iSAFE, that uses a statistic derived solely from population genetics signals to pinpoint the favored mutation even when the signature of selection extends to 5Mbp. iSAFE was tested extensively on simulated data and in human populations from the 1000 Genomes Project, at 22 loci with previously characterized selective sweeps. For 14 of the 22 loci, iSAFE ranked the previously characterized candidate mutation among the 13 highest scoring (out of ∼ 21, 000 variants). Three loci did not show a strong signal. For the remaining loci, iSAFE identified previously unreported mutations as being favored. In these regions, all of which involve pigmentation related genes, iSAFE identified identical selected mutations in multiple non-African populations suggesting an out-of-Africa onset of ...

Research paper thumbnail of Correction to: Transplantation of Human Chorion-Derived Cholinergic Progenitor Cells: a Novel Treatment for Neurological Disorders

Molecular neurobiology, Jan 26, 2018

The original version of this article unfortunately contained mistake in the affiliation. Affiliat... more The original version of this article unfortunately contained mistake in the affiliation. Affiliation 1 should be read as "Neuroscience Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran". The original article has been corrected.

Research paper thumbnail of Identifying the favored mutation in a positive selective sweep

Nature methods, 2018

Most approaches that capture signatures of selective sweeps in population genomics data do not id... more Most approaches that capture signatures of selective sweeps in population genomics data do not identify the specific mutation favored by selection. We present iSAFE (for "integrated selection of allele favored by evolution"), a method that enables researchers to accurately pinpoint the favored mutation in a large region (∼5 Mbp) by using a statistic derived solely from population genetics signals. iSAFE does not require knowledge of demography, the phenotype under selection, or functional annotations of mutations.

Research paper thumbnail of Purity determining of cultured OECs from olfactory mucosa of rats\' pups

Journal of Basic Research in Medical Sciences

Introduction: Cell transplantation is one of the main strategies for spinal cord injury repair. A... more Introduction: Cell transplantation is one of the main strategies for spinal cord injury repair. As OECs of the olfactory mucosa can be obtained by simple biopsy in all individuals without affecting their smell sensation, OECs considered as a promising candidate for autologous transplantation in the nervous system injury, especially for spinal cord repair. Thereby in the current study OECs were cultured from olfactory mucosa of 7 days old rats' pups and their purity was examined by flow-cytometry after simultaneous double staining for p75 and GFAP markers. Materials and methods: 7 days old Wistar rats' pups were deeply anesthetized by ketamine / xylazine (60/6mg/Kg). Then the nasal cavity was opened sagittally and the olfactory mucosa was separated from posterior part of nasal septum and at last OECs were obtained from lamina properia of olfactory mucosa and were cultured. The cultured cells were simultaneously immunolabeled for p75 and GFAP markers and finally purity of cultured cells assessed by flow-cytometry. Results: cultured OECs demonstrated two different morphologies, a spindle shape Schwannlike and an astrocyte-like OECs with flat sheet-like morphology. In addition, simultaneous immunolabeling for p75 and GFAP markers of OECs exhibited OECs were positive for both markers at the same time. The flow-cytometry results displayed that 87.9±2.4% of cells were p75/ GFAP double positive cells,1.05±0.4 only p75 positive and 5.8±1.5% were single positive for GFAP. Conclusion: Purity of cultured OECs in our study is probably more than 87.9% by flowowing to p75+/S100+ and GFAP+/S100+ olfactory ensheathing cells were not counted. Thus the culture procedure of this study seems to be a good protocol for OECs purifying and cell therapy in CNS damages.

Research paper thumbnail of The combined application of human adipose derived stem cells and Chondroitinase ABC in treatment of a spinal cord injury model

Neuropeptides, 2016

Although stem cell therapy has become a major focus as a new option for management of spinal cord... more Although stem cell therapy has become a major focus as a new option for management of spinal cord injury (SCI), its effectiveness should be promoted. In this study, we investigated the effects of co-administrating human adipose-derived stem cells (hADSCs) and Chondroitinase ABC (ChABC) in a rat model of spinal cord injury. hADSCs derived from superficial layer of abdominal adipose tissue were used to treat a contusion-induced SCI. Animals were randomly allocated to five equal groups including sham (only laminectomy), SCI (SCI+vehicle injection), hADSCs (1×10⁶ hADSCs/10μl intra-spinal injection), ChABC (10μl of 100U/ml ChABC intra-spinal injection injection), and hADSCs+ChABC. Basso, Beattie and Bresnahan tests were used to evaluate locomotor function. 8weeks after treatment, cavity size, myelination, cell differentiation (neuron and astrocyte), and chondroitin sulfate amount were analyzed. hADSC transplanted animals, ChABC injected animals (P<0.001), and hADSC+ChABC treated rats (P<0.001) displayed significant motor improvement compared to SCI group. Combination therapy of hADSCs and ChABC led to greater locomotor recovery compared to using hADSCs (P<0.001) or ChABC (P<0.01) alone. Spinal cords in the combined and single therapy groups had cavities filled with myelinated areas and less chondroitin sulfate content in comparison with the control group (P<0.001). hADSCs expressed GFAP, B III tubulin and Map2. Combination therapy with ChABC and hADSCs exhibits more significant functional recovery than single therapy using either. This result may be applicable in selection of the best therapeutic strategy for SCI.

Research paper thumbnail of Study of the effect of exogenous melatonin on sperm fertility in busulfan induced oligospermic of pinealectomeized rat

Razi Journal of Medical Sciences, Aug 15, 2013

Research paper thumbnail of The role of biodegradable engineered nanofiber scaffolds seeded with hair follicle stem cells for tissue engineering

Iranian biomedical journal, 2012

The aim of this study was to fabricate the poly caprolactone (PCL) aligned nanofiber scaffold and... more The aim of this study was to fabricate the poly caprolactone (PCL) aligned nanofiber scaffold and to evaluate the survival, adhesion, proliferation, and differentiation of rat hair follicle stem cells (HFSC) in the graft material using electrospun PCL nanofiber scaffold for tissue engineering applications. The bulge region of rat whisker was isolated and cultured in DMEM: nutrient mixture F-12 supplemented with epidermal growth factor. The morphological and biological features of cultured bulge cells were observed by light microscopy using immunocytochemistry methods. Electrospinning was used for production of PCL nanofiber scaffolds. Scanning electron microscopy (SEM), 3-(4, 5-di-methylthiazol- 2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, and histology analysis were used to investigate the cell morphology, viability, attachment and infiltration of the HFSC on the PCL nanofiber scaffolds. The results of the MTT assay showed cell viability and cell proliferation of the HFSC on...

Research paper thumbnail of Optimization of nose shape of Launch Vehicle using genetic algorithm and response surface methods

2009 4th International Conference on Recent Advances in Space Technologies, 2009

In this study, to reduce the drag force, the nose shape of Launch Vehicle with determined flight ... more In this study, to reduce the drag force, the nose shape of Launch Vehicle with determined flight conditions, is optimized. Two optimization methods are considered: binary genetic algorithm and response surface method. Since the value of drag coefficient is proportional to dynamic pressure, the objective function is based on minimization of drag coefficient in flight conditions which is corresponding to

Research paper thumbnail of Comparison of Human Adipose-Derived Stem Cells and Bone Marrow-Derived Stem Cells in a Myocardial Infarction Model

Cell Transplantation, 2014

Spinal cord injury (SCI) is one of the most serious clinical diseases and its treatment has been ... more Spinal cord injury (SCI) is one of the most serious clinical diseases and its treatment has been a subject of interest to researchers. There are two important therapeutic strategies in the treatment of SCI: replacing lost tissue cells through cells implantation and scar elimination. Therefore, in this study we used human adipose-derived stem cells (hADSCs) implantation and injection of Chondroitinase ABC. Aim of present study was to answer to this question: which one is more efficient for Improvement of locomotor recovery after SCI in rat? Transplantation of hADSCs or injection of ChABC. The spinal cord of rats was injured by contusion using a weight-drop at the level of T8-9, the hADSCs and Chondroitinase ABC were infused in to the spinal cord tissue after injury. BBB test was performed and recorded for each animal weekly for 8 weeks. After the 8(th) weeks, Serial cross-sections were stained with cresyl violet and examined under a light microscope and area of cavity in the spinal cord was measured. At 8(th) weeks after injection, hADSCs and ChABC significantly promote locomotor function (P<0.01) and spinal cords of hADSCs and ChABC group had cavities much smaller than those of the control group (P<0.001). Results of the present study shows dealing with inappropriate neuro-inhibitory environment and glial scar by ChABC have equal role compare to cell therapy (with hADSCs) for improving motor function after SCI and this result in adoption of proper therapeutic strategies for SCI intervention is important.

Research paper thumbnail of Co-transplantation of bone marrow stromal cells with schwann cells evokes mechanical allodynia in the contusion model of spinal cord injury in rats

Several studies have shown that, although transplantation of neural stem cells into the contusion... more Several studies have shown that, although transplantation of neural stem cells into the contusion model of spinal cord injury (SCI) promotes locomotor function and improves functional recovery, it induces a painful response, Allodynia. Different studies indicate that bone marrow stromal cells (BMSCs) and Schwann cells (SCs) can improve locomotor recovery when transplanted into the injured rat spinal cord. Since these cells are commonly used in cell therapy, we investigated whether co-transplantation of these cells leads to the development of Allodynia. In this experimental research, the contusion model of SCI was induced by laminectomy at the T8-T9 level of the spinal cord in adult female wistar rats (n=40) weighting (250-300g) using the New York University Device. BMSCs and SCs were cultured and prelabeled with 5-bromo-2-deoxyuridine (BrdU) and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) respectively. The rats were divided into five groups of 8 including: a control group (laminectomy only), three experimental groups (BMSC, SC and Co-transplant) and a sham group. The experimental groups received BMSCs, SCs, and BMSCs and SCs respectively by intraspinal injection 7 days after injury and the sham group received serum only. Locomotion was assessed using Basso, Beattie and Bresnahan (BBB) test and Allodynia by the withdrawal threshold test using Von Frey Filaments at 1, 7, 14, 21, 28, 35, 42, 49 and 56 days after SCI. The statistical comparisons between groups were carried out by using repeated measures analysis of variances (ANOVA). Significant differences were observed in BBB scores in the Co- transplant group compared to the BMSC and SC groups (p< 0.05). There were also significant differences in the withdrawal threshold means between animals in the sham group and the BMSC, SC and the Co-transplant groups (p<0.05).BBB scores and withdrawal threshold means showed that co-transplation improved functioning but greater Allodynia compared to the other experimental groups. The present study has shown that, although transplantation of BMSCs, SCs and a combination of these cells into the injured rat spinal cord can improve functional recovery, it leads to the development of mechanical Allodynia. This finding indicates that strategies to reduce Allodynia in cell transplantation studies are required.

Research paper thumbnail of Co-transplantation of bone marrow stromal cells with schwann cells evokes mechanical allodynia in the contusion model of spinal cord injury in rats

Several studies have shown that, although transplantation of neural stem cells into the contusion... more Several studies have shown that, although transplantation of neural stem cells into the contusion model of spinal cord injury (SCI) promotes locomotor function and improves functional recovery, it induces a painful response, Allodynia. Different studies indicate that bone marrow stromal cells (BMSCs) and Schwann cells (SCs) can improve locomotor recovery when transplanted into the injured rat spinal cord. Since these cells are commonly used in cell therapy, we investigated whether co-transplantation of these cells leads to the development of Allodynia. In this experimental research, the contusion model of SCI was induced by laminectomy at the T8-T9 level of the spinal cord in adult female wistar rats (n=40) weighting (250-300g) using the New York University Device. BMSCs and SCs were cultured and prelabeled with 5-bromo-2-deoxyuridine (BrdU) and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) respectively. The rats were divided into five groups of 8 including: a control group (laminectomy only), three experimental groups (BMSC, SC and Co-transplant) and a sham group. The experimental groups received BMSCs, SCs, and BMSCs and SCs respectively by intraspinal injection 7 days after injury and the sham group received serum only. Locomotion was assessed using Basso, Beattie and Bresnahan (BBB) test and Allodynia by the withdrawal threshold test using Von Frey Filaments at 1, 7, 14, 21, 28, 35, 42, 49 and 56 days after SCI. The statistical comparisons between groups were carried out by using repeated measures analysis of variances (ANOVA). Significant differences were observed in BBB scores in the Co- transplant group compared to the BMSC and SC groups (p< 0.05). There were also significant differences in the withdrawal threshold means between animals in the sham group and the BMSC, SC and the Co-transplant groups (p<0.05).BBB scores and withdrawal threshold means showed that co-transplation improved functioning but greater Allodynia compared to the other experimental groups. The present study has shown that, although transplantation of BMSCs, SCs and a combination of these cells into the injured rat spinal cord can improve functional recovery, it leads to the development of mechanical Allodynia. This finding indicates that strategies to reduce Allodynia in cell transplantation studies are required.