The Effect of Human Umbilical Cord-Derived Lyophilized Stem Cells on Fat Graft Viability: An Experimental Study.

OBJECTIVE: The extended use of autologous adipose tissue has increased the importance of the viability of fat graft cells. This experimental animal study assesses the effects of lyophilized mesenchymal stem cells on the viability and survival of autologous fat grafts. METHODS: For this prospective treatment control study, 27 male Wistar albino rats were divided into three groups, each containing nine animals. In Group 1 (control), an incision was made in the right inguinal region, and the skin was closed with 4/0 prolene sutures. In Groups 2 and 3, fat pads collected from the right groin of the rats were lipoaspirated and placed on the sternum as a subcutaneous fat graft. The skin was then closed with 4/0 prolene sutures. Saline was added to the fat grafts of the Group 2 (sham) rats, and placenta-derived mesenchymal stem cell lyophilizate (MSC-L) was administered to the fat graft in the Group 3 (treatment) rats. After three months of treatment, the adipose tissue harvested from Group 1 and the fat grafts taken from Groups 2 and 3 were assessed histopathologically, stereologically and biochemically. RESULTS: Adipose tissue volume was lower in Group 2 than in Groups 1 and 3, and the adipose tissue treated with MSC-L in Group 3 was better preserved than that in Group 1. Connective tissue and vascular volumes were greater in Group 3 than those in the other groups. The normal structures of adipocytes, fibrous tissues and vessels were better preserved in Group 3 than in Group 2, and a large number of new blood vessels were noted to have formed in Group 3. Damaged cystic cells, areas of calcification and degenerated adipocytes were noted in Group 2, while the G3PDH levels increased significantly more in Group 3 than in Group 2. CONCLUSION: It was shown that MSC-L treatment plays an active role in maintaining the volume and survival of fat grafts by promoting neovascularization in this animal experimental study. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Potential Effects of Stem Cells Derived from the Peripheral Nerve and Adipose Tissue after the Nerve Crush Injury in Control and Obese Rats.

Aim of this study is to investigate effects of stem cells derived from the peripheral nerve and adipose tissues following the nerve crush injury in control and obese rats. For this aim, 41 Wistar Albino female rats were separated into eight equal groups; non-obese control (NOC) obese control (OC), non-obese injury (NOH), obese injury (OH), non-obese adipose (NOY), obese adipose (OY), non-obese nerve (NOPS), obese nerve (OPS). At the end of 8 weeks, all experimental animals without control groups were subjected to nerve crush procedure and sciatic nerve or fat stem cell homogenates were injected on the treatment group rats, and then, recovery process has been observed and histopathological, stereological, electrophysiological analyses and bioinformatic evaluation were made on removed sciatic nerves. Stereological results showed that adipose homogenate gave more successful results than peripheral nerve homogenates in the NOY group in comparison to the NOPS group in terms of myelinated axon number. Peripheral nerve homogenate has shown more successful results in the OPS group in comparison to the OY group. The number of unmyelinated axons was increased following treatment with adipose tissue homogenate in NOY and OY groups. In terms of myelin sheath thickness; we detected that treatments by peripheral nerve and especially adipose tissue homogenates lead to increase in the thickness of the axons of the peripheral nerves belong to the control and obese injury groups. All results showed that mesenchymal stem cell treatment by fresh tissue homogenates is successful in peripheral nerve regeneration and fat tissue is a considerable source of the stem cells for clinical applications.

Is vagal stimulation or inhibition benefit on the regulation of the stomach brain axis in obesity?

Objective: Possible effects of the vagus inhibition and stimulation on the hypothalamic nuclei, myenteric plexes and the vagus nerve were investigated.Methods: The female rats divided to the inhibition (INH), stimulation (STI) and, sham (SHAM) groups were fed with high fat diet (including 40% of energy from animal fat). After nine weeks, the rats were allowed to recover for 4 weeks in INH group. In STI group, the left vagus nerve stimulated (30 Hz/500 msn/30 sec.) starting 2nd post operative day for 5 minutes during 4 weeks. Healthy female rats used as control (CONT). Then, tissue samples were analyzed by biochemical, histological and stereological methods.Results: The mean number of the neurons in the arcuate nucleus of the INH group was significantly less; but, that is significantly more in the STI group compared to the other groups. The neuronal density of ventromedial nucleus in the STI group was higher; while the density in the INH group was lower than the other groups. In the dorsomedial nucleus, neuron density of the INH group was lower than the other groups. In terms of the myenteric plexus volumes, that of the INH group was lowest. The myelinated axon number in the INH group was significantly highest. The myelin sheath thickness and axon area of the INH group was significantly lower than the other groups.Discussion: The results of the study show that the vagal inhibition is more effective than the vagal stimulation on the weight loss in the obesity.

A brief update on physical and optical disector applications and sectioning-staining methods in neuroscience.

A quantitative description of a three-dimensional (3D) object based on two-dimensional images can be made using stereological methods These methods involve unbiased approaches and provide reliable results with quantitative data. The quantitative morphology of the nervous system has been thoroughly researched in this context. In particular, various novel methods such as design-based stereological approaches have been applied in neuoromorphological studies. The main foundations of these methods are systematic random sampling and a 3D approach to structures such as tissues and organs. One key point in these methods is that selected samples should represent the entire structure. Quantification of neurons, i.e. particles, is important for revealing degrees of neurodegeneration and regeneration in an organ or system. One of the most crucial morphometric parameters in biological studies is thus the "number". The disector counting method introduced by Sterio in 1984 is an efficient and reliable solution for particle number estimation. In order to obtain precise results by means of stereological analysis, counting items should be seen clearly in the tissue. If an item in the tissue cannot be seen, these cannot be analyzed even using unbiased stereological techniques. Staining and sectioning processes therefore play a critical role in stereological analysis. The purpose of this review is to evaluate current neuroscientific studies using optical and physical disector counting methods and to discuss their definitions and methodological characteristics. Although the efficiency of the optical disector method in light microscopic studies has been revealed in recent years, the physical disector method is more easily performed in electron microscopic studies. Also, we offered to readers summaries of some common basic staining and sectioning methods, which can be used for stereological techniques in this review.

The neuroprotective effect of melatonin on the hippocampus exposed to diclofenac sodium during the prenatal period.

Melatonin (Mel) has strong antioxidant properties since it is a direct scavenger of oxygen-based free radicals and related species. The main aim of this study is to show whether the effects of Mel can prevent the potential adverse effects of diclofenac sodium (DS), used as a non-steroidal anti-inflammatory drug (NSAID) during the prenatal period, on the newborn experimental rat brain tissues using stereological methods Twenty-four male 12-week old Wistar albino rats were used. The study involved four groups (each containing six rats), those exposed, during the prenatal period, to saline 1ml/kg (Saline group), to diclofenac sodium 3.6mg/kg (DS group), or to diclofenac sodium+melatonin 50mg/kg (DS+Mel group), and a control group (Cont group). At the end of the experiment, the brains were removed from the cranium for histological and stereological analyses. Cell loss in the hippocampus exposed to DS was observed compared to the Cont group (p<0.01), and a similar side-effect was also seen in the Saline group (p<0.01). However, there was no significant difference in cell numbers between the Cont and DS+Mel groups (p>0.05). These results suggest that exposure to DS during pregnancy causes a decrease in the number of cells in the hippocampus and dentate gyrus in the postnatal period. Using Mel, a neuroprotective agent, reduced the toxic effects of DS.

Does omega-3 have a protective effect on the rat adrenal gland exposed to 900 MHz electromagnetic fields?

The aim of this study was to investigate the harmful effects of exposure to 900-megahertz (MHz) electromagnetic fields (EMF) and the protective effects of omega-3 (Omg-3) against EMF in the rat adrenal gland. Eighteen Wistar albino rats were randomly assigned into three groups, control (Cont), EMF, and EMF + Omg-3. The EMF and EMF + Omg-3 groups both consisted of six rats exposed to an EMF of 900 MHz for 60 min/day for 15 days. No procedure was applied to the six rats in the Cont group. At the end of the experiment, all rats were sacrificed, and the mean volumes of the cortex and medulla of the adrenal gland were estimated using a stereological counting technique. The stereological results showed that the mean volume of the adrenal gland increased significantly in the EMF-exposed groups compared to the Cont group. Additionally, the mean volume of the adrenal gland was significantly lower in the EMF + Omg-3 group compared to the EMF group. We suggest that Omg-3 therapy aimed at suppressing the effects of EMF may prove a safe alternative for animals, whether or not they are exposed to EMF.

Effects of electromagnetic fields exposure on the antioxidant defense system.

Technological devices have become essential components of daily life. However, their deleterious effects on the body, particularly on the nervous system, are well known. Electromagnetic fields (EMF) have various chemical effects, including causing deterioration in large molecules in cells and imbalance in ionic equilibrium. Despite being essential for life, oxygen molecules can lead to the generation of hazardous by-products, known as reactive oxygen species (ROS), during biological reactions. These reactive oxygen species can damage cellular components such as proteins, lipids and DNA. Antioxidant defense systems exist in order to keep free radical formation under control and to prevent their harmful effects on the biological system. Free radical formation can take place in various ways, including ultraviolet light, drugs, lipid oxidation, immunological reactions, radiation, stress, smoking, alcohol and biochemical redox reactions. Oxidative stress occurs if the antioxidant defense system is unable to prevent the harmful effects of free radicals. Several studies have reported that exposure to EMF results in oxidative stress in many tissues of the body. Exposure to EMF is known to increase free radical concentrations and traceability and can affect the radical couple recombination. The purpose of this review was to highlight the impact of oxidative stress on antioxidant systems. Abbreviations: EMF, electromagnetic fields; RF, radiofrequency; ROS, reactive oxygen species; GSH, glutathione; GPx, glutathione peroxidase; GR, glutathione reductase; GST, glutathione S-transferase; CAT, catalase; SOD, superoxide dismutase; HSP, heat shock protein; EMF/RFR, electromagnetic frequency and radiofrequency exposures; ELF-EMFs, exposure to extremely low frequency; MEL, melatonin; FA, folic acid; MDA, malondialdehyde.

Effects of folic acid on rat kidney exposed to 900 MHz electromagnetic radiation.

Because of increased use of cell phones, the purpose of this study was to investigation of the oxidative damage caused by electromagnetic radiation (EMR) emitted by cell phones and histological and morphometrical determination of the possible protective role of folic acid (FA) in preventing the detrimental effects of EMR on the kidney. Twenty-four adult male Wistar albino rats were divided into control (Cont), EMR, EMR + FA and FA groups, each containing six rats. The EMR and EMR + FA groups were exposed to EMR for 60 min a day over a period of 21 days, while no EMR exposure was applied to the Cont and FA groups. The source of the EMR was an EMR device which emits a digital signal producing 900-MHz frequency radiation. The generator connected to a one-monopole antenna was used in this study and the rats were placed in the plexiglass restrainer at an equal distance from the monopole antenna. Following the experimental period, and after tissue processing, a physical disector-Cavalieri method combination was applied to the sections. The mean volume of the cortex, medulla, proximal and distal tubules increased significantly in the EMR groups compared to the Cont group (p < 0.01). Contrarily, the total number of glomeruli in the EMR group decreased compared to the Cont group (p < 0.01). The protective effects of FA was observed in the kidney (p < 0.05). In conclusion, the 900-MHz EMR leads to kidney damage. FA may exhibit a protective effect against the adverse effects of EMR exposure in terms of the total number of glomeruli.

Effects of 900-MHz radiation on the hippocampus and cerebellum of adult rats and attenuation of such effects by folic acid and Boswellia sacra.

The radiation emitted from mobile phones has various deleterious effects on human health. This study was conducted to evaluate the effects of exposure to the 900-MHz radiation electromagnetic fields (EMF) emitted by mobile phones on Ammon's horn and the dentate gyrus (DG) in the hippocampus and cerebellum of male Wistar albino rats. We also investigated the neuroprotective effects of the antioxidants Boswellia sacra (BS) and folic acid (FA) against exposure to EMF. Twenty-four adult male rats were randomly divided into four groups of six animals each, an EMF group, an EMF + FA exposure group (EFA), an EMF + BS exposure group (EBS) and a control group (Cont). The EMF, EFA and EBS groups were exposed to 900-MHz EMF radiation inside a tube once daily over 21 days (60 min/day). The Cont group was not exposed to 900-MHz EMF. The results showed that EMF caused a significant decrease in total pyramidal and granular cell numbers in the hippocampus, and DG and in Purkinje cell numbers in the cerebellum in the EMF group compared to the other groups (p < 0.05). BS and FA attenuated the neurodegenerative effects of EMF in the hippocampus and cerebellum. Significant differences were also determined between the numbers of neurons in the EFA and EMF groups, and between the EBS and EMF groups (p < 0.05). However, there were no significant differences among Cont, EFA and EBS (p > 0.05). Our results may contribute to ongoing research into the effects of 900-MHz EMF exposure. Abbreviations: BS, Boswellia sacra; CA, cornu ammonis; CAT, catalase; CE, coefficient of error; CV, coefficient of variation; DG, dentate gyrus; DNA, deoxyribonucleic acid; EMF, electromagnetic field; EBS, the group that is exposed to EMF and received a single daily gavage of BS (500 mg/kg/day) during 21 days; EEG, electroencephalogram; EFA, the group that is exposed to EMF and received a single daily gavage of folic acid (50 mg/kg/day) during 21 days; FA, folic acid; gr, granular layer; H2O2, hydrogen peroxide; MHz, Megahertz; ml, molecular layer; RF, radiofrequency; ROS, reactive oxygen specimens; SEM, standard error of the mean.

The Use of Sequential VEGF- and BMP2-Releasing Biodegradable Scaffolds in Rabbit Mandibular Defects.

PURPOSE: Promising developments have materialized in reconstructive surgical procedures with the applications of tissue engineering. In our study, we used tissue scaffolds fabricated from polylactic acid-polyethylene glycol (PLLA-PEG) copolymers to ensure different release rates of selective growth factors recombinant human bone morphogenetic protein 2 [rhBMP-2] and vascular endothelial growth factor (rhVEGF165) in the repair of mandibular bone defects. MATERIALS AND METHODS: In our experimental study, 54 New Zealand rabbits were used. The rabbits were separated into 4 groups: group I (control group), PLLA-PEG scaffold only; group II, PLLA-PEG scaffold plus rhBMP-2 application; group III, PLLA-PEG scaffold plus VEGF165 application; and group IV, PLLA-PEG scaffold plus rhBMP-2 and VEGF165 applications. The rabbits were killed at 4 and 8 weeks postoperatively, and histopathologic and immunohistochemical assessments were performed. RESULTS: The greatest bone volume was observed in rhBMP-2-containing groups, the greatest vessel volume was observed in VEGF165-containing groups; however, the scaffold containing rhBMP-2 and VEGF165 provided the best outcomes in conjunction with increased remodeling of the new bone. CONCLUSIONS: The use of polymer tissue scaffolds that release rhVEGF165 and rhBMP-2 in coordination and mimic the natural healing process in the regeneration of especially complex tissues, such as bone, is a promising treatment alternative in the field of reconstructive surgery.

Effects of prenatal 900 MHz electromagnetic field exposures on the histology of rat kidney.

PURPOSE: To research the harmful effects of prenatal exposure of 900 megahertz (MHz) electromagnetic field (EMF) on kidneys of four-week-old male rats and to determine protective effects of melatonin (MEL) and omega-3 (ω-3). MATERIALS AND METHODS: Twenty-one Wistar albino rats were randomly placed into seven groups as follows: Control (Cont), Sham, MEL, ω-3, EMF, EMF+ MEL and EMF+ω-3. After mating, three groups (EMF, EMF+ MEL, EMF+ ω-3) were exposed to an EMF. In the fourth week subsequent to parturition, six rats were randomly chosen from each group. Mean volume of kidneys and renal cortices, the total number of glomeruli and basic histological structure of kidney were evaluated by stereological and light microscopical methods, respectively. RESULTS: Stereological results determined the mean volume of the kidneys and cortices were significantly increased in EMF-exposed groups compared to the Cont group. However, EMF-unexposed groups were not significantly modified compared to the Cont group. Additionally, the total number of glomeruli was significantly higher in EMF-unexposed groups compared to the Cont group. Alternatively, the number of glomeruli in EMF-exposed groups was decreased compared to the Cont group. CONCLUSIONS: Prenatal exposure of rat kidneys to 900 MHz EMF resulted in increased total kidney volume and decreased the numbers of glomeruli. Moreover, MEL and ω-3 prevented adverse effects of EMF on the kidneys.