Evaluation of the Biodistribution of Arginine, glycine, aspartic acid peptide-modified Nanoliposomes Containing Curcumin in Rats.

Background: Liposomes, as a biological membrane, is successfully used for drug delivery, reduces toxicity in normal cells and improves bio-accessibility of the drug to the target cells. Curcumin, as a bioactive substance with pleiotropic biological activities, is an anti-inflammatory compound and has several anticancer effects in different cancers such as pancreatic and breast cancer. Objectives: This study was conducted to determine the bio-distribution of arginine-glycine-aspartic acid (RGD)-modified nanoliposomes containing curcumin in different tissues of rats. Materials and Methods: The amount of curcumin in each tissue was examined by HPLC analysis. The distribution of liposomal Hoechst in the rats was evaluated by using fluorescence spectrophotometry, live animal imaging analyses and histological methods. Results: HPLC analysis showed the mean of curcumin in the blood significantly increased in the liposomal curcumin modified with RGD compared to free curcumin. These results were confirmed by fluorescence measurement for RGD modified liposome containing Hoechst dye. There was negligible fluorescent intensity in the blood rats, which received Hoechst alone. Live animal imaging analysis showed the presence of fluorescent color in heart tissue for all groups. It was also detected in kidney tissue for liposomal Hoechst modified with RGD group. Conclusions: The present study demonstrated that RGD-modified nano-liposomes can significantly improve drug retention time in the blood of rats.

Preparation and evaluation of polycaprolactone/chitosan/Jaft biocompatible nanofibers as a burn wound dressing.

Tissue engineering is an emerging method for replacing damaged tissues. In this study, the potential application of electrospun polycaprolactone/chitosan/ the internal layer of oak fruit (Jaft) as skin scaffolds was investigated. A combination of Polycaprolactone (PCL), chitosan (CH), and the internal layer of oak fruit (Jaft) was used to incorporate mechanical properties of synthetic polymers, biological properties of natural polymers, and antibacterial activity of Jaft. Physical and morphological characteristics of prepared scaffolds were investigated using a scanning electron microscope (SEM), mechanical analysis, swelling ratio, and contact angle. Moreover, chemical and biological properties were evaluated by Fourier-transform infrared spectroscopy (FTIR), chromatography, flow cytometry, DAPI staining, MTT assay, and trypan blue exclusion assay. Obtained results demonstrated that the fabricated scaffolds have good mechanical properties. Moreover, the addition of chitosan and Jaft to the PCL scaffolds improved their water absorption capacity as well as surface hydrophilicity. MTT results showed the fabricated nanofibrous scaffolds have adequate cell viability, which is higher than the cell culture plate at each time point of culture. Furthermore, SEM images of cultured scaffolds, trypan blue exclusion assay, and DAPI staining confirmed that fibroblast cells could be well-attached and proliferate on the PCL/CH/Jaft scaffolds. Results have proven that this novel bioactive scaffold has promising mechanical properties, suitable biocompatibility in vitro, and in vivo. Consequently, it could be a promising candidate for skin tissue engineering applications.

RGD peptide-mediated liposomal curcumin targeted delivery to breast cancer cells.

In this study, turmeric's active ingredient (Curcumin) was encapsulated into RGD modified Liposomes (RGD-Lip-Cur) its cytotoxic effect on the breast cancer cell line (MCF-7) was evaluated by MTT, flow cytometry and Caspase assay. Liposomes were characterized using transmission electron microscopy (TEM). Results demonstrated that the liposomes were spherical in shape, ranging from 70 to 100 nm. MTT assay revealed that RGD-Lip-Cur had a significant cytotoxic effect on MCF-7 cells at concentrations of 32, 16 and 4 µg/ml compared to Lip-Cur (P < 0.05) and curcumin (P < 0.01). The apoptosis assay demonstrated that RGD-Lip-Cur induces the apoptosis in MCF-7 cells (39.6% vs 40.2% for initial and secondary apoptosis) significantly more than Lip-Cur (67.7% vs 9.16% for initial and secondary apoptosis) and free curcumin (7.84% vs 38.8% for initial and secondary apoptosis). Moreover, caspase assay showed that RGD-Lip-Cur activates caspase 3/7 compared to Lip-Cur (P < 0.05) and free curcumin (P < 0.01). The RGD-Lip-Cur was similar to the control group and had no significant cytotoxicity effect. It is concluded that RGD-Lip-Cur as a novel carrier have high cytotoxicity effect on breast cancer cell line (MCF-7).

The Effect of Muscle Graft With Nerve Growth Factor and Laminin on Sciatic Nerve Repair in Rats.

INTRODUCTION: Peripheral nerve injury is one of the most common damages that lead to physical disability. Considering the similarity between the coatings of skeletal muscles and nerve fibers, we conducted this research to determine the effect of muscle graft with Nerve Growth Factor (NGF) and Laminin (L) on nerve repair. METHODS: We cut a 10-mm length of the sciatic nerve from 42 female Wistar rats (Weight: 200±250 g) and equally divided the rats into three groups. In the muscle graft+NGF+laminin group, the degenerated skeletal muscle was sutured with proximal and distal ends of the transected sciatic nerve. Then, NGF (100 ng) and laminin (1.28 mg/mL) were injected into the muscle graft. In the muscle graft group, normal saline was injected into the muscle graft. In the control group, 10 mm of the sciatic nerve was removed without any treatment. Functional recovery was assessed based on Sciatic Functional Index (SFI). Also, tracing motor neurons and histological studies were performed to evaluate nerve repair. The obtained data were analyzed by ANOVA test. RESULTS: The Mean±SD SFI value significantly increased in the muscle graft+NGF+laminin (-76.6±2.9) and muscle graft (-82.1±3.5) groups 60 days after the injury compared to the control group. The Mean±SD number of labeled motor neurons significantly increased in the muscle graft+NGF+laminin (78.6±3.1) and muscle graft (61.3±6.1) groups compared to the control group (P<0.001). The mean number of myelinated axons in the distal segments of the muscle graft+NGF+laminin increased significantly compared to the muscle graft group. CONCLUSION: These findings suggest that muscle graft followed by NGF and laminin administration have therapeutic effects on nerve repair.

A Review Study on Phytochemistry and Pharmacology Applications of Juglans Regia Plant.

In recent years, the use of medicinal plants increased considerably; so that today, the use of traditional medicine, as well as medicinal plants is necessary for the aim of producing more effective drugs with fewer side effects and determining the effective doses. With the scientific name of Juglans regia, walnut plant is a medicinal plant with different properties that is considered less, despite having great therapeutic potential in the traditional medicine. The aim of this study was to review the dispersal of walnut plants, the chemical compounds, and therapeutic effects of walnuts on antioxidant activity, antidiabetic, hypolipidemic, antimicrobial, and antihypertensive activities, as well as liver protection. Data of this review study have been collected from the books and scientific articles published in databases such as Science Direct, Web of Science, Scopus, PubMed, and Scientific Information Database. While this plant having high antioxidant capabilities, walnuts are composed of many chemical compounds such as ascorbic acid, flavonoids, quercetin, and caffeic acid. Experimental studies have shown that walnuts reduced blood glucose and lipids and also decreased blood pressure. They have antioxidant, antidiabetic, antimicrobial, and liver-protective properties. The use of walnuts in traditional medicine and review of experimental studies demonstrated the presence of multiple, effective, and useful compounds which may provide the opportunity for the production of lipid-lowering, antidiabetes, and liver protective drugs. Due to the effects of walnuts on improving the complications of various diseases, the need for doing comprehensive clinical trials for the use of walnuts in the treatment of diseases is necessary.

The Hydroalcoholic Extract of Matricaria chamomilla Suppresses Migration and Invasion of Human Breast Cancer MDA-MB-468 and MCF-7 Cell Lines.

BACKGROUND: Matricaria chamomilla is an aromatic plant with antioxidant, anticancer, and anti-inflammatory properties. However, the inhibitory role of M. chamomilla on migration and invasion of human breast cancer cells remains unclear. OBJECTIVE: This study investigated the methods to evaluate these anticancer mechanisms of M. chamomilla on human breast cancer MCF-7 and MDA-MB-468 cell lines. MATERIALS AND METHODS: The cells were treated with hydroalcoholic extract of M. chamomilla at different concentrations (50-1300 µg/mL) for 24, 48, and 72 h in a culture medium containing 10% fetal bovine serum. This study quantified the 50% growth inhibition concentrations (IC50) by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay; apoptosis and necrosis through Hoechst 33342/propidium iodide staining; cell proliferation and clone formation by clonogenic assay as well as cellular migration, invasion, and attachment. After 24, 48, and 72 h of treatment, the IC50levels were 992 ± 2.3 µg/mL, 893 ± 5.4 µg/mL, and 785 ± 4.8 µg/mL against MDA-MB-468, respectively, and 1288 ± 5.6 µg/mL, 926 ± 2.5 µg/mL, and 921 ± 3.5 µg/mL, against MCF-7, respectively. Furthermore, increasing the extract concentrations induced cellular apoptosis and necrosis and decreased cellular invasion or migration through 8 µm pores, colonization and attachment in a dose-dependent manner. RESULTS: It indicated time- and dose-dependent anti-invasive and antimigrative or proliferative and antitoxic effects of hydroalcoholic extract of aerial parts of chamomile on breast cancer cells. CONCLUSION: This study demonstrated an effective plant in preventing or treating breast cancer. SUMMARY: Antioxidant compounds in Matricaria chamomilla have anticancer effects.Hydroalcoholic extract of M. chamomilla controls cellular proliferation and apoptosis induction.Hoechst 33342/propidium iodide staining suggested that the extract induces apoptosis more than necrosis.Hydroalcoholic extract of M. chamomilla prevents colonization and cellular migration of human breast cancer MDA-MB-468 and MCF-7 cell lines in a time- and dose-dependent manner.M. chamomilla has low cytotoxic effects on natural cells. Abbreviations Used: IARC: International Agency for Research on Cancer; WHO: World Health Organization; FBS: Fetal bovine serum; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; DMSO: Dimethyl sulfoxide; PI: Propidium iodide; LN: Live cells with normal nucleus; LA: Live cells with apoptized nucleus; DN: Dead cells with normal nucleus; DA: Dead cells with apoptized nucleus; BSA: Bovine serum albumin; ANOVA: Analysis of variance; IC50: 50% growth inhibition concentration; GSE: Grape seed extract.

Pramipexole reduces inflammation in the experimental animal models of inflammation.

Pramipexole is a dopamine (DA) agonist (D2 subfamily receptors) that widely use in the treatment of Parkinson's diseases. Some epidemiological and genetic studies propose a role of inflammation in the pathophysiology of Parkinson's disease. To our knowledge, there is no study regarding the anti-inflammatory activity of pramipexol. Therefore, the aim of the study was to investigate anti-inflammatory effect of pramipexol. Anti-inflammatory effects of pramipexole were studied in three well-characterized animal models of inflammation, including carrageenan- or formalin-induced paw inflammation in rats, and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema in mice. The animals received pramipexol (0.25, 0.5 and 1 mg/kg, I.P.) 30 min before subplantar injection of carrageenan or formalin. Pramipexol (0.5 and 1 mg/kg) was also injected 30 min before topical application of TPA on the ear mice. Serum malondialdehyde (MDA) levels were evaluated in the carrageenan test. Finally, pathological examination of the inflamed tissues was carried out. Pramipexole significantly inhibited paw inflammation 1, 2, 3 and 4 h after carrageenan challenge compared with the control group (p < .001). Pramipexol also showed considerable anti-inflammatory activity against formalin-evoked paw edema over a period of 24 h (p < .001). TPA-induced ear edema was markedly decreased by pramipexol (p < .001). The pathological evaluation of the paws and ears revealed that pramipexole reduced tissue injury, neutrophil infiltration, and subcutaneous edema. Pramipexole did not alter the increased serum levels of MDA due to carrageenan injection. These data clearly indicate that pramipexol possesses significant anti-inflammatory activity. It seems that its antioxidants do not play an important role in these effects.

Comparison of repair of peripheral nerve transection in predegenerated muscle with and without a vein graft.

BACKGROUND: Despite substantial research into the topic and valiant surgical efforts, reconstruction of peripheral nerve injury remains a challenging surgery. This study was conducted to evaluate the effectiveness of axonal regeneration of a transected sciatic nerve through a vein conduit containing degenerated skeletal muscle compared with axonal regeneration in a transected sciatic nerve through degenerated skeletal muscle alone. METHODS: In two of the three experimental rat groups, 10 mm of the left sciatic nerve was transected and removed. The proximal and distal ends of the transected sciatic nerve were then approximated and surrounded with either (a) a degenerated skeletal muscle graft; or (b) a graft containing both degenerated skeletal muscle and vein. In the group receiving the combined vein and skeletal muscle graft, the vein walls were subsequently sutured to the proximal and distal nerve stump epineurium. Sciatic functional index (SFI) was used for assessment of functional recovery. Tracing study and histological procedures were used to assess axonal regeneration. RESULTS: At 60 days, the gait functional recovery as well as the mean number of myelinated axons in the middle and distal parts of the sciatic nerve significantly increased in the group with the vein graft compared to rats with only the muscular graft (P < 0.05). Mean diameter of myelinated nerve fiber of the distal sciatic nerve was also improved with the vein graft compared to the muscle graft alone (P < 0.05). The mean number of DiI-labeled motor neurons in the L4-L5 spinal segment increased in the vein with muscle group but was not significantly different between the two groups. CONCLUSIONS: These findings demonstrated that a graft consisting of not only predegenerated muscle, but also predegenerated muscle with vein more effectively supported nerve regeneration, thus promoting functional recovery after sciatic nerve injury in rats.

The Effects of L-arginine on the Hippocampus of Male Rat Fetuses under Maternal Stress.

INTRODUCTION: Prenatal stress has deleterious effects on the development of the brain and is associated with behavioral and psychosocial problems in childhood and adulthood. This study aimed to determine the protective effect of L-arginine on fetal brain under maternal stress. METHODS: Twenty pregnant Wistar rats (weighting 200-230 g) were randomly divided into 4 groups (n=5 for each group). The first nonstress and stress groups received 2 mL of normal saline and the other nonstress and stress two groups received L-arginine (200 mg/kg, IP) from their 5(th) to 20(th) days of pregnancy. The pregnant rats were killed on 20(th) day and the brain fetuses removed and prefrontal cortical thickness, total neurons in the prefrontal cortex and in the areas of CA1, CA2, and CA3 of the hippocampus were measured and counted. Nitrite levels in the brain were measured as an indicator for nitric oxide (NO) level. RESULTS: There was a significant decrease of mean number of pyramidal cells in the CA1 in prenatal stress group compared to nonstress and nonstress plus arginine groups. The NO level in brain tissue increased significantly in the stress plus arginine (3.8±0.4 nmol/mg) and in nonstress rats (2.9±0.3 nmol/mg) compared to the stress group (1.8±0.1 nmol/mg). Prefrontal cortical thickness decreased significantly in stress rats (1.2±0.09 mm) compared to the nonstress plus arginine (1.7±0.15 mm) and nonstress (1.6±0.13 mm) groups. DISCUSSION: Results indicated that prenatal stress could lead to neurodegeneration of hippocampus and prefrontal cortex of rat fetuses. L-arginine as a precursor of NO synthesis had neuroprotective effect during prenatal stress and could be used an effective treatment for stress.

The Effects of Medicago Sativa and Allium Porrum on Iron Overload in Rats.

PURPOSE: Iron overload may occur due to regular blood transfusions and high intestinal iron absorption. Currently, there is no effective drug without side effects for the treatment of iron excess in thalassemia and other iron storage diseases, except chelation therapy, which is the only safe method for iron excretion. Thus, scientists are more focused on medicinal plants rich in phytochemical compounds for the removal of iron in thalassemia. Therefore this study was managed to discover the therapeutic potential of hydro-alcoholic extract of Allium porrum and Medicago sativa for iron chelating potential. METHODS: Aerial parts of Allium porrum and Medicago sativa were collected in Yasuj Iran. Rats were divided into seven groups each containing six. Extracts were administrated in four groups (two groups for each extract) by single doses of each plant with 200 and 400 mg/kg body weight by (i.p.) route every other day for 28 days. Group 1 as negative control received saline (0.5 ml/kg) by (i.p.) route. Positive control received iron dextran 200 mg/kg body weight. Experimental groups 1 and 2 for each plant extract were fed with 200 and 400 mg/kg, hydro-alcoholic extract respectively via (i.p.) route, 1 h after the injection of iron dextran. Standard group was treated with deferoxamine (DF) 50 mg/kg by (i.p.) route 1 h after the injection of iron dextran. Serum iron (SI) and serum total iron binding capacity (TIBC) were determined .The serum ferritin was then measured using enzyme immunoassay ELISA kit for rat. For Analysis of data ANOVA test was used. RESULTS: Hydro-alcoholic extract of Medicago sativa and Allium porrum at 400 mg/kg showed significant (p<0.05) iron chelating activity compared to control. The plant extracts with dose 200 mg/kg also reduced the iron and ferritin content but the effect was lower level compared to higher doses. The plant extract effects were similar to that of standard drug deferoxamine. Iron and ferritin levels were significantly reduced in experimental groups when compared to positive group especially in Medicago sativap<0.05. There was no difference between standard drugs and last concentration of plant extracts. CONCLUSION: Protective effect of M. sativa and A. Porrum against iron overload in rat model was reported. Significant decrease in serum ferritin and iron concentration was reported in iron overload rats which induced by iron dextran.

Age-associated changes on axonal regeneration and functional outcome after spinal cord injury in rats.

This study was conducted to evaluate the association between aging and regenerative potential of spinal cord injury. Three groups of male Sprague-Dawley rats, including young (40 days), mature (5-6 months) and old (28-29 months) were spinally hemisected at the L1 level. The locomotor performance was assessed weekly for eight weeks after lesion using locomotors' rating scale developed by Basso, Bresnahan and Beattie (BBB). In the tracing study, retrograde labeled neuron was counted in the lateral vestibular nucleus for axonal regeneration. From 4-8 weeks, the functional recovery of the young and mature age rats was significantly increased in comparison to the old age group. At 8 weeks, young and mature animals achieved a plateau score of (mean ± SD), 17 ± 1.47 and 16.8 ± 0.70 respectively, and the old rats reached an average score of 13.8±1.63 (P<0.05). The mean number of labeled neurons in the vestibular nucleus in the young group (mean ± SD): 32.05 ± 1.03 increase significantly compared to the older age group 5.01 ± 1.31 (P<0.05). Current findings suggest that axonal repair and functional improvement decrease in aged animals after partial spinal cord injury. Thus, the aging process may affect the regenerative capacity of the injured central nervous system, and axonal regeneration is age dependent.

The effect of vitamin D on vaginal atrophy in postmenopausal women.

BACKGROUND: Most of the women suffer from vaginal atrophy and dryness, and therefore, efficient and safe treatment is needed to improve vaginal lubrication. Vitamin D has several important functions which may be effective in proliferation and repair of the epithelial tissue. This study aimed to evaluate the effect of vitamin D vaginal suppositories on maturation index, pH, and dryness in postmenopausal women. MATERIALS AND METHODS: Women were enrolled in this double-blind clinical trial, in whom menopause occurred at least one year ago. Those women who had an abnormal Papanicolaou smear, had undergone hormonal treatment, or have had vaginal infection in the previous year were excluded. Forty-four women who found eligible were randomized into two equal groups, the treatment and control groups, which received vitamin D and placebo vaginal suppository daily for 8 weeks, respectively. Vaginal pH and maturation value were measured at the beginning and end of the study. Pain, dryness, and paleness were assessed before treatment and at the end of the 2, 4, and 8 weeks of treatment. RESULTS: In the treatment group, the number (Mean ± SD) of superficial cells increased (69.76 ± 12.4) and vaginal pH decreased (1.42 ± 0.67) significantly compared to the control group after 56 days. The mean pain significantly reduced after 8 weeks in the treatment group (1.23 ± 0.53) compared to the control group 1.95 ± 0.74 (P < 0.001). The mean of dryness and paleness reduced significantly in the treatment group versus control at 56 days. CONCLUSIONS: Vitamin D is effective in improving the maturation index and decreased the pH and dryness of the vaginal atrophy due to menopause.

Cell therapy in spinal cord injury: a mini- reivew.

Spinal cord injury (SCI) is a debilitating disease which leads to progressive functional damages. Because of limited axonal regeneration in the central nervous system, there is no or little recovery expected in the patients. Different cellular and molecular approaches were investigated in SCI animal models. Cellular transplantation of stem cells can potentially replace damaged tissue and provide a suitable microenvironment for axons to regenerate. Here, we reviewed the last approaches applied by our colleagues and others in order to improve axonal regeneration following SCI. We used different types of stem cells via different methods. First, fetal olfactory mucosa, schwann, and bone marrow stromal cells were transplanted into the injury sites in SCI models. In later studies, was applied simultaneous transplantation of stem cells with chondroitinase ABC in SCI models with the aid of nanoparticles. Using these approaches, considerable functional recovery was observed. However, considering some challenges in stem cell therapy such as rejection, infection, and development of a new cancer, our more recent strategy was application of cytokines. We observed a significant improvement in motor function of rats when stromal derived factor-1 was used to attract innate stem cells to the injury site. In conclusion, it seems that co-transplantation of different cells accompanies with other factors like enzymes and growth factors via new delivery systems may yield better results in SCI.

The effects of cyclosporin-A on functional outcome and axonal regrowth following spinal cord injury in adult rats.

It has been shown that the immunophilin ligands have the special advantage in spinal cord repair. In this study, the effects of cyclosporine A (CsA) on functional recovery and histological outcome were evaluated following spinal cord injury in rats. After spinal cord hemisection in thirty six adult female Sprague-Dawley rats (200- 250 g), treatment groups received CsA (2.5 mg/kg i.p.) at 15min and 24h after lesion (CsA 15min group and CsA 24h group) daily, for 8 weeks. Control and sham groups received normal saline and in sham operated animals the spinal cord was exposed in the same manner as treatment groups, but was not hemisected. Hindlimb motor function was assessed in 1, 3, 5 and 7 weeks after lesion, using locomotive rating scale developed by Basso, Bresnahan and Beattie (BBB). Motor neurons were counted within the lamina IX of ventral horn and lesion size was measured in 5 mm of spinal lumbar segment with the epicenter of the lesion site. The mean number of motor neurons and the mean BBB scale in 3, 5 and 7 weeks in CsA 15min groups significantly increased compared to the control group. Although, the lesion size reduced in rats with CsA treatment compared to the control group, no significant difference was observed. Thus, it can be concluded that CsA can improve locomotor function and histological outcome in the partial spinal cord injury.

The effect of hydro alcoholic extract of Juglans regia leaves in streptozotocin-nicotinamide induced diabetic rats.

Phytotherapy has been achieved to maintain glycemic control in patients with diabetes mellitus. The present study was conducted to evaluate the antihyperglycemic properties of the Juglans regia leaf extract in streptozotocin-nicotinamide induced diabetic rats. Nicotinamide was injected intraperitonealy (i.p.) 15 min before the injection of Streptozotocin (i.p.). One week after induction of diabetes, oral treatment started with extract of Juglans regia and Metformin and continued for 4 weeks. Fasting blood sugar, body weight, serum lipids and insulin level were measured in different groups. A significant reduction of glucose, HbA1c, total cholesterol and serum triglycerides were detected after 4 weeks in rats treated with Juglans regia leaves compared to the control groups. Thus, Juglans regia extract treatment showed potential hypoglycemic and hypolipidemic effects in type 2 diabetic rats.

Ultrastructural changes in spinal motoneurons and locomotor functional study after sciatic nerve repair in conduit tube.

OBJECTIVES: Motor deficit and neuron degeneration is seen after nerve transection. The aim of this study is to determine whether a poled polyvinelidene fluoride (PVDF) tube with other supportive strategies can protect the neuronal morphology and motor function after sciatic nerve transaction in rats. MATERIALS AND METHODS: After transection of the left sciatic nerve in 60 male Wistar rats (200-250 g), the epineural group was sutured end to end. In the autograft rats, a 10 mm piece of sciatic nerve was rotated 180 °C and sutured back into the nerve gap. In the nerve guidance channel (NGC) group, polarized piezoelectric PVDF tube containing NGF and collagen gel was sutured in the gap. In control group sciatic nerve was removed (10 mm) without repair. After one, four and eight weeks, the L4-L6 spinal cord segment was removed for histological study using transmission electron microscope. Functional outcome was assessed using the Basso, Bresnahan and Beattie (BBB) locomotor scale at both four and eight weeks after the lesion. RESULTS: Chromatin condensation was seen after 4 weeks in the repair groups. Cell membrane shrinkage and mitochondrial degeneration was observed after 4 and 8 weeks respectively, in the autografted and NGC rats. In the control group, chromatin condensation, cell membrane shrinkage with mitochondrial degeneration and vacuolization of perikaryon was seen after 1, 4 and 8 weeks, respectively. At 56 days, the functional recovery of the epineural rats significantly increased in comparison to the other groups (P< 0.05). CONCLUSION: The epineural suture has more efficacies, and NGC may be used as a proper substitute for autograft in nerve injury.

Repair of peripheral nerve defects using a polyvinylidene fluoride channel containing nerve growth factor and collagen gel in adult rats.

OBJECTIVE: As effectiveness of the autologous graft in the repair of long nerve defects is very limited an effective substitute is needed. This study was conducted to determine the poled polyvinylidene fluoride (PVDF) tube as an alternative to nerve autograft. MATERIALS AND METHODS: The left sciatic nerve was transected in 45 male Wistar rats. The animals were then divided randomly into three groups: in an epineural group the nerve was sutured end to end; in an autograft group a 10 mm piece of sciatic nerve was cut, rotated 180° and sutured in the nerve gap; and in a nerve guidance channel group (NGC), PVDF, tube containing nerve growth factor (NGF) and collagen gel was placed in the gap. In a control (n=15) group the sciatic nerve was exposed but not transected. To determine axonal regeneration, retrograde DiI tracer was injected into the gastrocnemius muscle. One week later, retrograde-labeled neurons were counted in the L4-L6 spinal segments and one way ANOVA analysis was performed to compare groups. Neuronal morphology changes were studied by electron microscopy. RESULTS: Significant statistical decreases in the mean number of labeled motoneurons were observed in all surgical groups compared to the control group; and in the autograft and the NGC groups compared to epinural suture group (p<0.01). No significant difference in the mean number of motoneurons was observed between the autograft and NGC groups. Chromatin condensation, dilated endoplasmic reticulum and large vacuoles were observed in the autograft and NGC groups. CONCLUSION: Regarding the positive effects of PVDF tube containing NGF and Collagen gel on the sciatic nerve regeneration, authors suggest that it may be useful in peripheral nerve repair.

Transplantation of olfactory mucosa improve functional recovery and axonal regeneration following sciatic nerve repair in rats.

BACKGROUND: Olfactory ensheathing glia (OEG) has been shown to have a neuroprotective effect after being transplanted in rats with spinal cord injury. This study was conducted to determine the possible beneficial results of olfactory mucosa transplantation (OMT) which is a source of OEG on functional recovery and axonal regeneration after transection of the sciatic nerve. METHODS: In this study, 36 adult female Sprague-Dawley rats were used. The sciatic nerve was transected in 24 rats and immediately repaired by sciatic-sciatic anastomosis, and randomly divided equally into two groups. The experimental group received the OMT at the transected site and the control group received the respiratory mucosa transplant. In another twelve rats as sham-operated animals, the sciatic nerve was exposed but no transection was made. DiI retrograde tracing was injected in the gastrocnemius muscle two months after surgery to allow visualization of the extent of axonal regeneration. Functional recovery was also assessed at 15, 30, 45 and 60 days after surgery using walking track analysis and sciatic function index (SFI) calculations. RESULTS: The total number of DiI labeled motorneurones in the ventral horn (L4-L6) and the SFI scores were significantly higher in the group of rats that received olfactory mucosa rather than respiratory mucosa. CONCLUSIONS: The outcome indicates that olfactory mucosa is a useful treatment to improve nerve regeneration in mammals with peripheral nerve injury.