Effects of litter size and caging on physical and mental development in rats.

As a multidisciplinary field, laboratory animal science promotes or accelerates the emergence of innovative ideas and products. As research has increased, so has the demand for laboratory animals with reliable, standardized characteristics. Thus, the breeding, reproduction, and welfare of laboratory animals are now animals reliable and more. The aim of this study to investigate whether different litter sizes of mothers and different husbandry methods affect the physical and mental development of pups. 30 adults female Wistar Hanover albino rats weighing 200-250 g were used for the study. The weight of the pups was measured once a week from birth until the end of the study, and their physical development was observed. After the pups were weaned, they were randomly divided into cages by sex. The 45 male and 45 female pups were housed in groups of three, five, and seven per cage. When the pups were 12 weeks old, open field test, elevated plus-maze test and Morris water maze behavioral tests were performed every other day, and then plasma corticosterone levels were measured. When the male and female pups in the groups were 14 weeks old, six females were taken from each housing group and mated, and the conception rates and maternal behavior of the pups were observed. During lactation, physical developmental parameters and the body weight of the rats were affected by litter size. Among the post-weaning housing groups, cage density was found to affect weight gain and body weight between groups. It was found that only the sex factor caused significant differences in the behavior of the animals. Females housed with seven rats per cage had higher corticosteroid levels than other females. As a result, it was observed that cages with seven female rats were more physically and psychologically affected than those with three and five rats.

Alpha lipoic acid attenuates iron induced oxidative acute kidney injury in rats.

Iron has been implicated in oxidative tissue injury owing to its ability to generate reactive oxygen species (ROS). We investigated the reno-protective effects of alpha lipoic acid (ALA) by investigating its effects on the kidney isoform of NADPH oxidase (Nox4) and the specific signaling pathways, p38 MAPK and PI3K/Akt, which participate in apoptosis and survival, respectively. We established four groups of seven rats: control, 100 mg/kg ALA, 80 mg/kg iron sucrose (IS) and IS + ALA. IS and ALA were injected intravenously and rats were sacrificied after 6 h. The mRNA expression of the subunits of NADPH oxidase, Nox4 and p22phox; tumor necrosis factor-alpha (TNF-α); and kidney injury molecule-1 (KIM-1) were measured using quantitative real time polymerase chain reaction (qRT-PCR). Active caspase-3 protein expression was evaluated by immunostaining. Also, p38 MAPK and PI3K/Akt signaling pathways were analyzed using western blot. ALA suppressed the mRNA expression of Nox4, p22phox, TNF-α and KIM-1. Active caspase-3 protein expression induced by IS was decreased by ALA. ALA also suppressed p38 MAPK and activated the PI3K/Akt signaling pathway following IS administration. We found that ALA may be an effective strategy for preventing oxidative acute kidney injury caused by IS.

Neuroprotective Effects of Lacosamide and Memantine on Hyperoxic Brain Injury in Rats.

In neonates supraphysiological oxygen therapy has been demonstrated to cause neuronal death in hippocampus, prefrontal cortex, parietal cortex, and retrosplenial cortex. There is a need for the detection of novel neuroprotective drugs. Neuroprotective effects of lacosamide or memantine have been demonstrated in adult patients with ischemia, trauma and status epilepticus. The effects in immature brains may be different. This study aimed to evaluate neuroprotective effects of lacosamide and memantine treatment in a hyperoxia-induced brain injury model in immature rats. This study was performed in the Animal Experiments Laboratory of Dokuz Eylul University Faculty of Medicine. Neonatal Wistar strain rat pups were exposed to hyperoxia (80% oxygen + 20% nitrogen) for five days postnatally. They were divided into five groups; hyperoxia + lacosamide, hyperoxia + memantine, hyperoxia + lacosamide and memantine, hyperoxia + saline, control groups. After termination of the experiment, brain tissues were examined. Neuron counting in examined regions were found to be higher in hyperoxia + memantine and hyperoxia + lacosamide and memantine groups than hyperoxia + saline group. The presence of apoptotic cells evaluated with TUNEL and active Caspase-3 in hyperoxia + memantine and hyperoxia + lacosamide and memantine groups were found to be lower compared to hyperoxia + saline group. This study demonstrates that neuron death and apoptosis in newborn rat brains after hyperoxia is reduced upon memantine treatment. This is the first study to show the effects of memantine and lacosamide on hyperoxia-induced damage in neonatal rat brains.

Renoprotective Effects of Alpha Lipoic Acid on Iron Overload-Induced Kidney Injury in Rats by Suppressing NADPH Oxidase 4 and p38 MAPK Signaling.

We aimed to investigate the protective effect of alpha lipoic acid (ALA), a powerful antioxidant, against oxidative kidney damage induced by iron overload in rats. Male Wistar albino rats were separated into groups: control (n = 7), ALA (100 mg/kg (n = 7), iron sucrose (IS) (40 mg/kg) (n = 7), and IS + ALA (40 mg/kg IS administration followed by 100 mg/kg ALA) (n = 7). IS and ALA were injected weekly for 4 weeks via the tail vein. Blood and kidneys were collected at sacrification on day 29. Serum creatinine and iron levels were analyzed. Tubular injury and iron deposits were evaluated histopathologically. Additionally, iron, malondialdehyde (MDA), superoxide dismutase (SOD), catalase, and glutathione (GSH) levels and mRNA expressions of the subunits of NADPH oxidase, known as NOX4 and p22phox, tumor necrosis factor (TNF)-α, kidney injury molecule-1 (KIM-1), and also p38 MAPK signaling in the kidneys, were evaluated biochemically. In the IS group, serum creatinine and iron level, tubular dilation, and loss of brush border in the kidneys were significantly higher than those of the control. Although those changes were reduced by ALA, the differences were not statistically significant. However, ALA reduced significantly MDA level and increased SOD activity in the kidney during IS administration. ALA also significantly reduced mRNA expressions of NOX4 and p22phox induced by IS, which was parallel to significant decreases of TNF-α and KIM-1 mRNA expressions. Moreover, ALA could suppress the activation of p38 MAPK during IS administration. In conclusion, ALA may be an effective strategy to attenuate in IS-induced oxidative kidney injury.

Effects of adipose and bone marrow-derived mesenchymal stem cells on vaginal atrophy in a rat menopause model.

BACKGROUND & OBJECTIVES: Vaginal atrophy is characterized by thinning of vaginal epithelial layers and decreased local blood flow. We aimed to evaluate the regenerative effects of Adipose derived mesenchymal stem cells (ADMSC) and Bone marrow derived mesenchymal stem cells (BMDSC) on vaginal atrophy in rat menopause model. MATERIALS AND METHODS: Rats were randomly divided into 4 (four) groups: sham, control, ADMSC, BMDSC. Vaginal epithelial thickness, structure of the lamina propria, blood vessels in the lamina propria, collagen deposition, and muscle structure were evaluated. Anti ER α, VEGF, VEGFR 1, Bax and bcl-2 antibodies were analyzed. Beta actin gene was used as endogenous control. Genetical differences among the groups were compared by using Kruskal Wallis and Mann Whitney U test. p < 0.05 was regarded as statistically significant. RESULTS: Epithelial thickness of ADMSC group was higher than control group, but less than sham group Epithelial thickness of BMDSC group was less than sham group. Lamina propria and muscle tissue of ADMSC and BMDSC groups were found to be similar to sham group. VEGFR-1, VEGF, Bax and ER-α staining levels were higher in ADMSC and BMDSC groups than control group. ADMSC group stained stronger with VEGFR-1 and VEGF than BMDSC group. Bcl-2 staining level was increased in ADMSC applied group. No statistically significant difference was detected in Bax and Bcl-2 genes and Bax-/Bcl-2 ratio. CONCLUSIONS: Although genetic expression might have ended and could not be significantly demonstrated, histological and immunohistochemical results favor ADMSC application in vaginal atrophy rather than BMDSC.

Dexamethasone-loaded chitosan-based genipin-cross-linked hydrogel for prevention of cisplatin induced ototoxicity in Guinea pig model.

OBJECTIVES: The aim of this study was to investigate the protective effects of a sustained release form of dexamethasone (dex) loaded chitosan-based genipin-cross-linked hydrogel (CBGCH) in a guinea pig model of cisplatin (CP) induced hearing loss. METHODS: Implantation of CBGCH was made by intratympanic (IT) injection. Ototoxicity was produced by intraperitoneal (IP) single dose of 14 mg/kg CP. Animals were randomly divided into four groups with 6 guinea pigs in each. Group 1 received only IP CP; group 2 received only IT dex-loaded CBGCH injections. Group 3 and group 4 received IP CP, plus IT nondrug CBGCH and IT dex-loaded CBGCH respectively 24 h prior to IP CP injections. Distortion product otoacoustic emissions (DPOAEs) and auditory brainstem response (ABR) measurements were obtained before the treatments and solely ABR measurements were done after 3 and 10 days. The ultrastructural effects were investigated by scanning electron microscopy (SEM) analysis. RESULTS: The postCP ABR thresholds at 4, 8, 12, 16, 32 kHz frequencies were significantly better in group 4 than groups 1 and 3 (p < 0.05). The comparison of time effective ABR thresholds between groups 1 and 4 and between groups 3 and 4 showed significantly lower ABR thresholds in group 4 (p < 0.05). The SEM analysis showed that stereocilia of inner and outer hair cells were preserved in group 4, almost like group 2, whereas cytotoxic degenerations were noted in groups 1 and 3. CONCLUSIONS: Intratympanic administration of dex-loaded CBGCH has been shown to provide functional and structural protection against CP-induced ototoxicity.

Neuroprotective effects of MK-801 against traumatic brain injury in immature rats.

Traumatic brain injury (TBI) is a major health problem in pediatric ages and also has major social, economic, and emotional outcomes, with diverse sequelae in many spheres of everyday life. We aimed to investigate the effect of MK-801, a competitive NMDA receptor antagonist, on hippocampal damage and behavioral deficits on 10-day-old rat pups subjected to contusion injury. The aims of the present study were to determine: (i) the short term effects of MK-801 on hippocampal BDNF, NGF and NMDA receptor immunoreactivity and neuron density in hippocampus (ii) long term effects of MK-801 on cognitive dysfunction following TBI in the immature rats. MK-801, was injected intraperitoneally at the doses of 1mg/kg of body weight immediately after induction of traumatic injury. Hippocampal damage was examined by cresyl violet staining, BDNF, NGF and NMDAR receptor immunohistochemistry on P10 day and behavioral alterations were evaluated using elevated plus maze and novel object recognition tests two months after the trauma. Histopathological and immunohistochemical evaluations showed that treatment with a single dose of 1mg/kg MK-801 (i.p.) significantly ameliorated the trauma induced hippocampal neuron loss and decreased BDNF, NGF and NMDAR expressions in CA1, CA3 and DG hippocampal brain regions. Additionally, treatment with MK-801 ameliorated anxiety and hippocampus dependent memory of animals subjected to trauma. These results show that acute treatment of MK-801 has a neuroprotective role against trauma induced hippocampal neuron loss and associated cognitive impairment in immature rats.