The effects of Garcinia kola and curcumin on the dorsal root ganglion of the diabetic rat after peripheral nerve transection injury.

OBJECTIVE: To test the protective effects of Garcinia kola and curcumin on the ganglion tissues of diabetic rats following the use of autologous vein graft in peripheral nerve transection injury. METHODS: The sciatic nerve on the right side was transected, and anastomosis was performed between the proximal and distal ends using an autologous vein graft. Curcumin and Garcinia kola seed extract were administered daily by oral gavage. The ganglion tissues were harvested after a 90-day waiting period. Sensory neurons in the dorsal root ganglion at the L4 and L5 levels were used for stereological evaluations. Mean sensory neuron numbers were analyzed using a stereological technique. The size of the light and dark neurons was also estimated, and ultrastructural and immunohistochemical evaluations were performed. RESULTS: A statistically significant difference in sensory neuron numbers was observed between the groups with and without Garcinia kola and curcumin applications. The immunohistochemical results showed that the s-100 protein is expressed selectively between cell types. CONCLUSION: The results of this study show that curcumin and Garicinia kola prevented sensory neuron loss in diabetic rats following transection injury to the sciatic nerve.

The potential protective effects of melatonin and omega-3 on the male rat optic nerve exposed to 900 MHz electromagnetic radiation during the prenatal period.

BACKGROUND: Due to children and adolescents' widespread use of electronic devices, researchers have focused on pre-and early postnatal electromagnetic field (EMF) exposure. However, little is known about the effects of EMF exposure on the optic nerve. The aim of study was to investigate the changes occurring in the optic nerve and the protective effects of melatonin (mel) and omega 3 (ω-3) in rats. METHODS: Thirty-five pregnant rats were divided into seven groups, Cont, Sham, EMF, EMF + melatonin (EMF + Mel), EMF + ω3, Mel, and ω3. The EMF groups were exposed to 900 megahertz (MHz) EMF daily for two hours during pregnancy. After the experiment, the right optic nerve of each offspring rat was removed and fixed in glutaraldehyde. Thin and semi-thin sections were taken for electron microscopic and stereological analyses. Myelinated axon numbers, myelin sheath thicknesses, and axonal areas were estimated using stereological methods. RESULTS: The groups had no significant differences regarding mean numbers of axons, mean axonal areas, or mean myelin sheath thicknesses (p > 0.05). Histological observations revealed impaired lamellae in the myelin sheath of most axons, and vacuolization was frequently observed between the myelin sheath and axon in the EMF-exposed group. The Mel and ω-3-treated EMF groups exhibited well-preserved myelinated nerve fibers and intact astrocytes and oligodendrocytes. CONCLUSIONS: At the ultrastructural level, Mel and ω3 exhibits a neuroprotective effect on the optic nerve exposed to prenatal EMF. The protective effects of these antioxidants on oligodendrocytes, which play an essential role in myelin formation in the central nervous system, now require detailed investigation.

Effects of Topically Applied Contractubex® on Epidural Fibrosis and Axonal Regeneration in Injured Rat Sciatic Nerve.

AIM: To investigate the effects of Contractubex® (Cx) on peripheral nerve regeneration and scar formation. MATERIAL AND METHODS: A surgical procedure involving sciatic nerve incision in 24 adult male Sprague-Dawley rats followed by epineural suturing was performed. In weeks 4 and 12 following surgery, macroscopic, histological, functional, and electromyographic examinations of the sciatic nerve were conducted. RESULTS: No significant difference was found between the Cx group and the control group in terms of sciatic function index (SFI) and distal latency results at week 4 (p > 0.05). However, significant improvements in the Cx group were observed in SFI amplitudes and nerve action potentials at week 12 (p < 0.001 and p < 0.001, respectively). Significant improvements were found in the amplitudes of nerve action potentials in the treatment group after weeks 4 and 12 (p < 0.05 and p < 0.001, respectively). Macroscopically and histopathologically, epidural fibrosis decreased (p < 0.05 and p < 0.001, respectively). For both measurement times, the treatment group had significantly higher numbers of axons (week 4, p < 0.05; week 12, p < 0.001), and the treatment group had better results regarding its axon area (weeks 4 and 12, p < 0.001) and myelin thickness (weeks 4 and 12, p < 0.05). CONCLUSION: Cx, which is applied topically in peripheral nerve injury, affects axonal regeneration and axonal maturation positively and reduces the functional loss.

Immunolocalization of Fertilin ß, IZUMO1, and P34H in Ram Spermatozoa.

According to various reports, current methods of sperm freezing destroy the integrity of the sperm plasma membrane and acrosome. This study aimed to determine the changes in the existence and location of three proteins, namely fertilin ß, IZUMO1, and P34H, in ram spermatozoa. By using frozen-thawed spermatozoa, ejaculated fresh spermatozoa, and testicular and epididymal spermatozoa (obtained from caput, corpus, and caudal regions), the localizations of the mentioned proteins were performed using signal labeling with indirect immunofluorescence, and the quantification of these proteins was compared using Western blot analyses. Moreover, protein localization and signal labeling in fresh and frozen-thawed spermatozoa subjected to in vitro capacitation and acrosome reaction were compared. Using chlortetracycline (CTC) staining, as expected, it was detected that after incubating for 4 hours under capacitating conditions related to the control sample (0 hour), capacitated and acrosome-reacted sperm were increased (p < 0.001). Frozen-thawed samples had a lower density and expression than the ejaculate samples. Expression was not obtained, except for IZUMO1, from samples that underwent in vitro capacitation/acrosome reactions. Expression of IZUMO1 was seen as an increasing band formation from the equatorial region through the acrosome, after in vitro capacitation. However, after the acrosome reaction, the band formation was only on the equatorial region. Region-specific differences of proteins at the kDa level were obtained using Western blot analysis and possible isoforms specific to ram spermatozoa or proteins with similar epitopes were expressed. Considering the changes in surface proteins in frozen-thawed sperm, it is suggested that fertilin ß and P34H can be used as fertility or freezability markers.

Investigation of the in vitro cytotoxic effects and wound healing activity of ternary composite substance (hollow silica sphere/gum arabic/methylene blue).

We aimed to test the adsorption of the methylene blue (MB) on HSEPCGUM as a dye and also to test the obtained ternary biocomposite substance (HSEPCGUM-MB) on wound healing. Hollow silica spheres (HSS) are used in the pharmaceutical and biochemical field, because of low toxic, highly biocompatible and mechanically stable by large surface areas. HSS was obtained by mechanochemistry method. The obtained HSS was treated with epichlorohydrin to carry out an epoxidation process (HSEPC). Then, HSEPC was functionalized by treatment with gum arabic (HSEPCGUM). MB was adsorbed onto HSEPCGUM and the adsorption maximum capacity of HSEPCGUM (Xmax) was obtained 333 mg g-1. For in vitro studies, according to the cytotoxicity test results, ternary biocomposite substance (HSEPCGUM-MB) was studied at non-cytotoxic concentrations 10, 50 and 100 µg/ml and wound closure was found as 55% (100 µg/ml) as compared to control.

Effects of cepae extract, allantoin, and heparin mixture on developing andalready formed epidural fibrosis in a rat laminectomy model.

BACKGROUND/AIM: The study was designed to investigate whether local administration of a mixture composed of cepae extract, allantoin, and heparin (CAH) decreased already formed epidural fibrosis (EF) at the laminectomy site. MATERIALS AND METHODS: Twenty-four adult male Sprague Dawley rats were equally divided into four groups. Laminectomy was performed at the L5 level in all rats. The group 2 and group 4 rats were treated with local drug administration. While the group 1 and 2 rats were sacrificed after 6 weeks, the remaining rats were reoperated and CAH mixture was applied in group 4. The vertebral columns of all rats were removed en bloc. Fibroblast numbers, EF, and arachnoidal involvement (AI) were evaluated. RESULTS: The results of the treatment groups were separately compared with the control groups. The numbers of fibroblasts in the treatment groups were significantly lower than those in the control groups (P < 0.001). The grade of EF in group 2 was significantly less than that in group 1 (P < 0.05). There was no statistically significant difference regarding EF and AI grade between group 3 and group 4, and local application of the drug on EF and AI yielded better results than in the control groups. CONCLUSION: The mixture composed of CAH might be a successful candidate for preventing EF in clinical practice.

Does glioblastoma cyst fluid promote sciatic nerve regeneration?

Glioblastoma cyst fluid contains growth factors and extracellular matrix proteins which are known as neurotrophic and neurite-promoting agents. Therefore, we hypothesized that glioblastoma cyst fluid can promote the regeneration of injured peripheral nerves. To validate this hypothesis, we transected rat sciatic nerve, performed epineural anastomosis, and wrapped the injured sciatic nerve with glioblastoma cyst fluid- or saline-soaked gelatin sponges. Neurological function and histomorphological examinations showed that compared with the rats receiving local saline treatment, those receiving local glioblastoma cyst fluid treatment had better sciatic nerve function, fewer scars, greater axon area, counts and diameter as well as fiber diameter. These findings suggest that glioblastoma cyst fluid can promote the regeneration of injured sciatic nerve and has the potential for future clinical application in patients with peripheral nerve injury.

The effects of ankaferd blood stopper and microporous polysaccharide hemospheres on epidural fibrosis in rat laminectomy model.

PURPOSE: To investigate whether topically administered hemostatic agents ankaferd blood stopper and microporous polysaccharide hemospheres can decrease epidural fibrosis after laminectomy in rats. METHODS: Eighteen adult male Sprague-Dawley rats were equally and randomly divided into three groups. In the treatment groups, ankaferd blood stopper and microporous polysaccharide hemospheres topically administrated upon duramater surface after laminectomy. Fibroblast count, epidural fibrosis and arachnoidal involvement were evaluated and graded histopathologically. RESULTS: Our data revealed that the count of fibroblasts, the grading of epidural fibrosis and arachnoideal involvement in the rats treated with microporous polysaccharide hemospheres were significantly less than the control group. Although the arachnoideal involvement in ankaferd blood stopper group were significantly less than the control group, there were no statistical differences when comparing the grading of epidural fibrosis and the fibroblasts count between the treatment groups and the control group. CONCLUSION: The ankaferd blood stopper and microporous polysaccharide hemospheres reduced epidural fibrosis and arachnoideal involvement after laminectomy in rats.

Comparison between flexible collagen and vein conduits used for size-discrepant nerve repair: an experimental study in rats.

Primary nerve repair is the gold standard in nerve reconstruction. When primary repair is not possible for injured nerves, conduit-assisted repair methods are frequently used. As conduits, autologous vein segments or allogenic biodegradable products can be used. However, their effectiveness when used in a nerve defect where a size discrepancy exists has not been compared. In this study, either a vein graft or a synthetic collagen conduit was used to bridge 10-mm defects between size-discrepant tibial and peroneal nerves in a rat model. After 90 days, nerve regeneration was evaluated using electrophysiological and histological methods. It can be concluded based on the results of this study that bridging a 10-mm nerve gap with synthetic collagen conduits and autologous vein grafts yielded similar results in small-to-large nerve coaptations, with the vein graft being slightly more effective.

The role of oxidative stress and inflammatory response in high-fat diet induced peripheral neuropathy.

OBJECTIVE: Earlier studies suggest that high-calorie diet is an important risk factor for neuronal damage resulting from oxidative stress of lipid metabolism. In our experimental study of rats under high-fat diet, oxidative stress markers and axonal degeneration parameters were used to observe the sciatic nerve neuropathy. The aim of this study is to evaluate the pathophysiology of neuropathy induced by high-fat diet. METHODS: A total of 14 male rats (Wistar albino) were randomly divided into two experimental groups as follows; control group (n=7) and the model group (n=7); while control group was fed with standard diet; where the model group was fed with a high-fat diet for 12 weeks. At the end of 12 weeks, the lipid profile and blood glucose levels, interleukin-1ß (IL-1), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and transforming growth factor-ß (TGF-ß) levels were studied. Tissue malondialdehyde (MDA), nitric oxide (NO) levels and super-oxide dismutase (SOD), paraoxonase-1 (PON-1) and glutathione peroxidase (GPx) activities were studied. The distal blocks of the left sciatic nerves were evaluated for histomorphological analysis (including mean axon area, axon numbers, nerve fiber diameters, axon diameters, and thickness of myelin sheets). RESULTS: Body weights, serum glucose and high-density lipoprotein (HDL) levels of rats were found not statistically significantly different compared between the model and the control groups (p>0.05). Serum cholesterol, triglyceride, TGF-ß and TNF-α levels were significantly higher in the model group when compared with the control group (p<0.05). IL-1 and IL-6 levels were not statistically significantly different compared between the model group and the control group (p>0.05). The MDA and NO levels and the SOD and GPx activities of the sciatic nerves in model group were statistically significantly higher than the control group (p<0.05). In addition, the activities of PON-1 were statistically significantly lower in the model group when compared with the control group (p<0.05). The difference in the total number of myelinated axons between the control group and the model group was not statistically significant (p>0.05). The nerve fiber diameter and the thickness of the myelin sheet were statistically significantly lower in the model group when compared with the control group (p<0.05). The axon diameter and area were significantly decreased in the model group when compared with the control group (p<0.05). CONCLUSION: Our results support that dyslipidemia is an independent risk factor for the development of neuropathy. In addition, we postulated that oxidative stress and inflammatory response may play an important role in the pathogenesis of high-fat diet induced neuropathy.

The effect of prenatal exposure of a non-steroidal anti-inflammatory drug on the optic nerve of female rats: a stereological, histological, and electron microscopic study.

OBJECTIVE: Non-steroidal anti-inflammatory drugs (NSAIDs) can have adverse effects for in both mother and fetus following administration during the prenatal period. If given during pregnancy, diclofenac sodium (DS), an NSAID, is given during the pregnancy, may also affect the development of the central nervous system (CNS) or related structures. METHODS: Pregnant rats were separated into pure control (PG), saline (SG) and diclofenac groups (DG). A daily dose of 1 mg/kg of DS and 1 mL/kg saline was injected intraperitoneally to the DG and SG groups, respectively, from the 5th gestation day for a 15 day of period; the PG group received no treatment. After spontaneous delivery, female offspring were obtained from all groups. After the 20th week of postnatal life, the animals (n = 6 for each group) were perfused and the right optic nerves were resected. Sections were subjected to stereological and histological analysis. RESULTS: There were no significant differences (p > 0.05) between PG, SG and DG groups with respect to myelin thickness, axonal cross-sectional area, axon numerical density, total section area of optic nerve and axon number. CONCLUSIONS: Histological and stereological results indicated that treatment with DS or saline produced undesirable effects on female rat optic nerve development and myelinization with respect to morphology.

Prenatal exposure of diclofenac sodium affects morphology but not axon number of the median nerve of rats.

The present study examined the effect of DS exposure on median nerve development in rats during prenatal life. Pregnant female rats were divided into three groups: a control group, a saline group and a DS group. Offspring of these animals were divided into 2 subgroups: 4 weeks old and 20 weeks old. Nerve samples were taken from the right legs and evaluated using stereological techniques in terms of the axon number, axon cross-sectional area, and myelin thickness. No drug-dependent macroscopic abnormality was observed in the nerve. No differences were noted for axon number in the control, saline, and DS groups of the same age and gender. No gender difference was found for axon number or axon area between the other matched groups. In conclusion, prenatal exposure to diclofenac sodium does not affect axon number in rats, but can alter the morphology of the male and female median nerve.

The effect of melatonin and platelet gel on sciatic nerve repair: an electrophysiological and stereological study.

Nerve regeneration after surgical reconstruction is far from optimal, and thus effective strategies for improving the outcome of nerve repair are being sought. In this experiment, we verified if postoperative intraperitoneal melatonin (MLT) administration after intraoperative platelet gel application improves peripheral nerve regeneration. In adult male rats, 1-cm long sciatic nerve defects were repaired using four different strategies: autologous nerve graft repair followed by MLT (NM, n = 5), collagen conduit repair followed by MLT (CM, n = 5), platelet gel-enriched collagen conduit repair followed by MLT (CGM, n = 6), and platelet gel-enriched collagen conduit (CG, n = 5) repair followed by no substance administration. Sham operated animals were used as controls (Cont, n = 5). Ninety days after surgery, the nerve regeneration outcome was comparatively assessed by means of electrophysiological and stereological analysis. Electrophysiology revealed no significant differences between the experimental and the sham control groups. Stereological analysis showed no significant differences among the experimental groups regarding axon size and myelin thickness, but the axon number was significantly lower in the CM compared to Cont and NM group. Moreover, there was no significant difference between number of axons in CG and Cont groups, between CGM and CM, and between CM and NM. Although it was observed that platelet gel have a positive effect on nerve regeneration, but a combination of local platelet gel with MLT does not have the same effect on nerve repair.

Platelet gel does not improve peripheral nerve regeneration: an electrophysiological, stereological, and electron microscopic study.

Although use of platelet gel (PG) for promoting tissue regeneration is a popular approach because of its capacity to accelerate tissue regeneration, to our knowledge, its effects on peripheral nerve have still not been elucidated. Therefore, the aim of this study was to investigate effects of PG on sciatic nerve regeneration using electrophysiology, stereology, and electron microscopy. The study was performed using five groups of rats: sham operated (Sham), collagen tube conduit (CT), collagen tube conduit plus platelet gel (CT + PG), autogenous nerve graft (ANG), and primary repair (PR) groups. Gap length for CT and CT + PG groups is 1 cm. Electrophysiology showed that nerve conduction velocity was not different among experimental groups; the amplitude of compound action potential of PR group was significantly higher than other groups. Examination of the nerves showed that Sham group not only had a larger axon diameter but also a thicker myelin sheath. A higher number of myelinated axon was found in both ANG and PR groups in comparison to Sham, CT, and CT+PG groups. There is no significant difference between morphological quantities of CT+PG and CT group. It was expected that regeneration degree of the nerve fibers of CT+PG group would be better than CT group, which was the control group permitting to disclose the presence of a positive effect of PG on nerve regeneration, but this was not the case. Therefore, our results suggest that PG does not improve axon regeneration after microsurgical reconstruction of a nerve gap by collagen tubes.

Prenatal exposure to a non-steroidal anti-inflammatory drug or saline solution impairs sciatic nerve morphology: a stereological and histological study.

The toxic effect of non-steroidal anti-inflammatory drugs (NSAIDs) during development has been widely investigated. While it has been shown that these drugs impair central nervous development and compromise the neural activity, the effects of these substances on the development of peripheral nerves are still not clarified. In the present study, sciatic nerves withdrawn from three experimental groups of 4-week-old rats, prenatally exposed to either saline solution, or diclofenac sodium, and controls not exposed to any substance, were evaluated in terms of axon number, cross-sectional area of axon and myelin sheet thickness as well as of the ultrastructure of nerve fibers. Comparisons of stereological estimations among these three groups showed that axon number and mean axon cross-sectional area, but not average myelin sheet thickness, were significantly decreased in rats that were exposed to both diclofenac sodium and also to the saline solution, in comparison of the control group. Electron microscope analysis revealed, in both treated groups, deterioration of myelin sheaths that was more pronounced in rats that were exposed to diclofenac sodium. Altogether, these findings show that the prenatal administration of both diclofenac sodium and saline solution impairs peripheral nervous system development, thus suggesting that this potential teratogenic effect should be also taken into consideration in the clinical use of these substances in pregnant patients.

Sertoli cell proliferation during the post hatching period in domestic fowl.

There has been no study aimed at directly determining of the periods of Sertoli cell proliferation in birds even domestic fowl. The aims of this study were to observe the cessation of post-hatching mitotic proliferation of Sertoli cells in domestic fowl, and to determine the volume density of Sertoli and germ cells during this period. A total of 50 Leghorn chicks were used in this study. The testes sections of the animals were immunostained with BrdU to observe the proliferation of cells from one to 10 weeks of age. The volume density of the Sertoli and germ cells were determined using the standard point counting method. The volume density of the germ cell nuclei was initially less than that of the Sertoli cells but the volume density converged by week 6, and remained relatively constant until the commencement of meiosis. Clear labeling of Sertoli and germ cells was observed from week 1 to week 7. The only those cells still labeled after 8 weeks were germ cells, indicating that Sertoli cell proliferation had ceased. Therefore, it is recommended that any research into the testes of domestic fowl should consider the cessation of Sertoli cell proliferation by approximately 8 weeks.