Antiproliferative and Mitochondrial Protective Effects of Apigenin in an Oxygen-Induced Retinopathy In Vivo Mouse Model.

Purpose: To investigate the effects of a common dietary flavonoid apigenin on retinal endothelial cell proliferation, retinal morphological structure, and apoptotic cell death in an oxygen-induced retinopathy (OIR) mouse model to evaluate the possibility of the use of apigenin in the treatment of ocular neovascular diseases (ONDs). Methods: Ninety-six newborn C57BL/6J mice were included. Eight groups were randomized, each including 12 mice. Two negative control groups were kept in room air: the first without any injection and the second received intravitreal (IV) dimethyl sulfoxide (DMSO), which is the solvent we used. The OIR groups were exposed to 75% ± 2% oxygen from postnatal days (PD) 7 to 12. On PD 12, the mice were randomly assigned to 6 groups: 2 OIR control groups (1 received no injection, 1 received IV-DMSO), 2 IV-apigenin groups (10 and 20 µg/mL), and 2 intraperitoneal (IP)-apigenin groups (10 and 20 mg/kg). We quantified retinal endothelial cell proliferation by counting neovascular tufts in cross-sections and examined histological and ultrastructural changes through light and electron microscopy. We evaluated apoptosis by terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL). Results: We detected a significant increase in endothelial cell proliferation in the OIR groups. Groups receiving apigenin, both IP and IV, had significant decreases in endothelial cells, atypical mitochondrion count, and apoptotic cells compared with the groups receiving no injections. None of the apigenin-injected groups revealed cystic degeneration or cell loss. Conclusions: Apigenin suppresses neovascularization, has antiapoptotic and antioxidative effects in an OIR mouse model, and can be considered a promising agent for treating OND. Clinical trial (Project number: DA15/19).

The efficiency of propranolol on occurrence and development of 4-nitroquinoline 1-oxide-induced squamous cell carcinoma of the tongue in rats.

AIMS: The aim of this study to investigate the efficiency of propranolol on occurrence and development of 4-nitroquinoline 1-oxide (4NQO)-induced squamous cell carcinogenesis of the tongue in rats. SUBJECTS AND METHODS: The sample was composed of 27 male Sprague Dawley rats that received 50 ppm 4NQO for 20 weeks in drinking water. Group 1 (n = 9) was treated with 50 mg/kg/day propranolol for 20 weeks, Group 2 (n = 9), after carcinogenesis inducement for 20 weeks, received propranolol (50 mg/kg/day) for 2 weeks and Group 3 (n = 9) received no treatment. At the end of the experimental stage, the tongue specimens were evaluated under a light microscope and categorized as low- or high-risk lesions according to a binary system. STATISTICAL ANALYSIS USED: The statistical comparison was performed with a likelihood ratio test. RESULTS: Histopathological analysis revealed the risk of malignant transformation rates as 33.3% in Group 1, 55.5% in Group 2 and 77.8% in Group 3; however, the difference between the groups was not statistically significant (P > 0.05). CONCLUSION: The results of the study suggest that propranolol has a tendency to preventive effect against carcinogenesis.

Preventive and therapeutic effects of relaxin on bisphosphonate related osteonecrosis of the jaw: an experimental study in rats / Efeitos preventivos e terapêuticos da relaxina na osteonecrose da mandíbula relacionada a bisfosfonatos: um estudo experimental em ratos

Objective: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a challenging complication of chronic bisphosphonate (BP) use. The hormone relaxin is able to induce the multistep differentiation process of human osteoclastogenesis, exhibits antifibrotic and anti-inflammatory actions, and promotes vasodilatation, wound healing, and angiogenesis. The present study aimed to evaluate the effects of relaxin in the prevention and management of BRONJ. Material and Methods: Thirty-six male Sprague Dawley rats were randomly divided into four groups. Rats in group 1 (n = 10) received relaxin and BP simultaneously for 12 weeks. Rats in group 2 (n = 10) received injections of BP for 12 weeks, followed by relaxin for another 12 weeks. Rats in group 3 (n = 10) received only BP injections, and those in group 4 (control, n = 6) received only saline. Necrosis and inflammation in the rats' mandibles were evaluated as indicators of BRONJ. Results: Necrosis and inflammation were not detected in group 1 (BP + relaxin). In group 3 (BP only), incidence rates of necrosis and inflammation were 90% and 60%, respectively. Conclusions: Our findings suggest that relaxin may be potently effective in preventing BRONJ and have some benefit in the treatment of existing BRONJ (AU)

Objetivo: A osteonecrose da mandíbula relacionada ao bisfosfonato (BRONJ) é uma desafiadora complicação do uso crônico de bisfosfonato (BP). O hormônio relaxina é capaz de induzir o processo múltiplo de diferenciação da osteoclastogênese humana, exibe ações anti-fibróticas e anti-inflamatórias e promove vasodilatação, cicatrização de feridas e angiogênese. O presente estudo teve como objetivo avaliar os efeitos da relaxina na prevenção e tratamento do BRONJ. Material e Métodos: Trinta e seis ratos Sprague Dawley machos foram divididos aleatoriamente em quatro grupos. Os ratos do grupo 1 (n = 10) receberam relaxina e BP simultaneamente por 12 semanas. Os ratos do grupo 2 (n = 10) receberam injeções de BP por 12 semanas, seguidos de relaxina por mais 12 semanas. Os ratos do grupo 3 (n = 10) receberam apenas injeções de BP e os do grupo 4 (controle, n = 6) receberam apenas solução salina. Necrose e inflamação nas mandíbulas dos ratos foram avaliadas como indicadores de BRONJ. Resultados: Necrose e inflamação não foram detectadas no grupo 1 (BP + relaxina). No grupo 3 (somente BP), as taxas de incidência de necrose e inflamação foram de 90% e 60%, respectivamente. Conclusões: Nossos resultados sugerem que a relaxina pode ser potentemente eficaz na prevenção do BRONJ e ter algum benefício no tratamento do BRONJ existente.(AU)

Evaluation of New Baskent University Preservation Solution for Kidney Graft During Cold Ischemia: Preliminary Experimental Animal Study.

OBJECTIVES: Organ damage due to long cold ischemia time remains a hurdle in transplantation. In this preliminary animal study, we compared the new Baskent University Preservation Solution (BUPS) with the University of Wisconsin (UW) and histidine-tryptophan-ketoglutarate (HTK) solutions. MATERIALS AND METHODS: BUPS composition included electrolytes, raffinose, mannitol, N-acetylcysteine, taurine, adenosine, and ascorbic acid. In experiment 1, kidneys from 50 male Sprague-Dawley rats were placed into BUPS, HTK, or UW solution to assess cold ischemia injury, with biopsies taken at different time points for pathologic evaluation. In experiment 2, to investigate ischemia-reperfusion injury, 5 rats were renal transplant donors to 10 rats and 6 pigs were used as transplant donors-recipients among each other. RESULTS: In experiment 1, no significant cellular injury was shown at up to 3 hours of perfusion with any solution. At 6- to 48-hour perfusion, tubular injury was shown, with lowest injury in BUPS and HTK versus UW and control groups (P < .01). The BUPS group showed more moderate degree of tubular apoptosis and cytoskeletal rearrangement than the HTK and UW groups at 12-, 24-, and 48-hour perfusion (P < .01). In experiment 2, after ischemia-reperfusion injury, no significant differences were found between HTK and BUPS groups regarding tubular damage. Although no significant differences were shown regarding tubular cytoskeletal rearrangment and apoptosis in pig reperfusion group with BUPS versus HTK, significant differences were shown with these solutions in other groups. CONCLUSIONS: Tubular damage during ischemia-reperfusion injury (cytoskeletal disruption, increased apoptosis) were lower with BUPS. BUPS can be a cost-effective perfusion solution in transplantation.

Antiproliferative and anti-apoptotic effect of astaxanthin in an oxygen-induced retinopathy mouse model.

OBJECTIVE: To evaluate the impact of intravitreal (IV) and intraperitoneal (IP) astaxanthin (AST) injections on neovascular development (ND), retinal morphology, and apoptotic activity in a C57BL/6J mouse model with hyperoxia-induced retinopathy (HIR). DESIGN: C57BL/6J mouse model. METHODS: Two negative control groups (n = 6 each; one of which received IV sterile dimethyl sulfoxide [DMSO]) of C57BL/6J-type mice were exposed to room air. The HIR groups included 36 C57BL/6J-type mice exposed to 75% ± 2% oxygen from postnatal day (PD) 7 to PD 12. On PD 12, these mice were randomized into 6 groups (n = 6 each): 2 HIR control groups (one of which received IV-DMSO), 2 IV-AST groups (10 and 100 µg/mL), and 2 IP-AST groups (0.5 and 5 mg/kg). We measured ND by counting neovascular tufts in cross sections and examined histological, ultrastructural changes via light and electron microscopy. Apoptosis was detected using terminal deoxynucleotidyl transferase-mediated nick end-labeling. RESULTS: No ND was detected in the negative control groups. ND levels were not significantly different between high- and low-dose AST for either means of administration. However, ND levels were significantly lower in the AST groups, regardless of delivery, compared to the control groups. The means of delivery (IP versus IV) also yielded significant differences in ND. The incidence of mitochondrial dysmorphology and apoptosis were lower in groups receiving AST. CONCLUSIONS: AST seems to suppress ND and has anti-apoptotic activity in the HIR mouse model.

Technique of Ileobladder and Kidney Transplant in Rats and Pigs.

OBJECTIVES: Kidney transplant is the best choice for treatment of patients with advanced chronic renal disease. However, small, poorly compliant, and unstable bladders can result in major problems for patients. Here, we aimed to develop and evaluate a new ileobladder model. MATERIALS AND METHODS: Fifteen rats (250-300 g) and 5 pigs (~100 kg) were cared for according to institutional and published guidelines. After general anesthesia, laparotomy was done through midline incision. Ileal loops were prepared for ileobladder. After cystectomy (0.5 cm above the trigone in rats, 1 cm above the trigone in pigs), anastomoses were done between antimesenteric sides of ileal loops and bladder remnant with 6/0 Prolene suture. Three other pigs received simultaneous renal transplant. RESULTS: One rat died on day 1 postsurgery from multiorgan hemorrhage. Two rats survived for 5 days, 3 rats for 7 days, and 3 rats for 11 days; 6 rats were killed for pathologic evaluation after 3 months. One pig survived for 22 days and 1 for 9 days. Of the 3 pigs that received a simultaneous renal transplant, 2 pigs were alive and doing well 80 and 72 days after surgery with normal urinary discharge (1 pig was killed for pathologic evaluation after 3 days). When ileobladder was opened, complete recovery of the anastomosis line was observed. Pathologic examination of the anastomosis sites reported a normal healing process with moderate inflammation and the muscular wall of the intestine showed hypertrophia that nearly reached the size of the bladder muscularis propria. CONCLUSIONS: Although we had some complications because no draining procedure was used, in terms of technique, our new ileobladder model is promising for providing functional bladder volume. A larger scale series in the clinical setting is planned. This technique can be useful for small bladders and bladder physiology disorders.

Radiological and Histological Evaluation of the Effects of Cortical Perforations on Bone Healing in Mandibular Onlay Graft Procedures.

BACKGROUND: Perforations of the cortical bone may be an advantage for the success of the autogenous bone graft procedure, but whether this perforation has a positive effect on the bone remains controversial. PURPOSE: This study evaluates the effects of cortical perforation of the autogenous bone block graft radiologically and histologically. MATERIALS AND METHODS: Seven adult pigs were used for this study. On the experimental side, cortical perforation at the host site was prepared, while no perforation was done on the control side. The specimens were evaluated, and the Wilcoxon signed-rank test was used for statistical analysis. RESULTS: In the radiological evaluation, the Wilcoxon signed-rank test indicated no significant differences in densities among the grafts (p = .23) with a mean of 4.29 ± 0.951 for the unperforated graft side and 3.57 ± 0.976 for the decorticated graft side. In histological evaluation, there was a significant difference in the thickness of the grafts between the groups (experimental group 3.71 ± 1.286, control group: 4.71 ± 0.488; p = .033). However, when the remodeling and osteoblastic activity in the grafts were measured, no significant differences were observed between the groups (p = 1 and p = .133, respectively). CONCLUSION: In augmentation with mandibular onlay bone grafts, cortical perforations in the recipient site make no distinct contribution to bone healing within 12 weeks.

The effect of oophorectomy on epidural fibrosis after laminectomy: an experimental study in rats.

OBJECTIVE: The aim of this study was to examine the effect of oophorectomy in the formation of epidural fibrosis in a rat laminectomy model. METHODS: Thirty-six 12-month-old adult female Sprague-Dawley rats were used in this study. Rats were evenly divided into two groups; oophorectomized and sham-operated. Bilateral oophorectomy was performed on the 18 rats in the oophorectomized group. Three weeks after oophorectomy, rats in both groups underwent complete bilateral laminectomy at the L2 and L3 vertebral levels. Rats were divided into 3 equal groups and sacrificed in groups of 4 at the 4th, 8t, and 12th weeks postoperatively and the lumbar spine excised en bloc, fixed and decalcified. Sections were stained with hematoxylin and eosin and Masson's trichrome were used to evaluate epidural fibrosis, acute inflammation, chronic inflammation, and vascular proliferation. RESULTS: The mean histological sum grade of the epidural fibrosis was greater in the oophorectomized group (p>0.05). CONCLUSION: Endogenous estrogen could have an effect on epidural fibrosis formation after lumbar laminectomy in rats.

Protective effects of melatonin and octreotide against radiation-induced intestinal injury.

PURPOSE: To compare the protective effects of the potent antioxidants, melatonin and octreotide, against radiation-induced intestinal injury. METHODS: A total of 42 male 3-month-old Swiss albino mice (40 ± 10 g) were matched according to body weight and randomly assigned to one of six groups: control; radiation treatment (RT) only; melatonin only (15 mg/kg, i.p.); melatonin + RT; octreotide only (50 µg/kg i.p.); and octreotide + RT. Intestinal damage was induced by exposure to a single whole-body radiation dose of 8 Gy. All mice tolerated the experimental interventions, and no deaths were observed. RESULTS: Irradiation induced architectural disorganization, including inflammatory mononuclear cell infiltration, villitis, and desquamation with eosinophilic necrosis, and diminished mucosal thickness, crypt height, and villous height. In the melatonin + RT and octreotide + RT groups, the villous pattern was well preserved; desquamation at villous tips and edema was prominent, but necrosis was absent. The radiation-induced decrease in mucosal thickness was significantly reduced by pretreatment with melatonin (p < 0.001) or octreotide (p = 0.01), although the protective effect was significantly greater for melatonin (p = 0.04). Pretreatment with melatonin also preserved villous height (p = 0.009) and crypt height (p = 0.03); although a similar trend was observed for pre-irradiation octreotide, the differences were not significant. CONCLUSIONS: Melatonin and octreotide potently protected against radiation-induced intestinal injury in mice, but melatonin was significantly more effective in preserving the histological structure of the intestines, a finding that warrants confirmation in clinical studies.

Biomechanical and histological comparison of the influence of oestrogen deficient state on tendon healing potential in rats.

Thirty-six female Sprague-Dawley rats were divided into two groups: oophrectomised (oestrogen deficient) rats and sham operated (oestrogen maintained) rats. Rats were sacrificed at six, ten, and 14 weeks. The rats were randomly chosen to have biomechanical evaluation on one side and histological evaluation on the other. Biomechanical testing was performed on an Instron machine to measure peak load. Histological sections were evaluated for cell proliferation, collagen-fibre organisation, fibroblast density, angiogenesis, inflammatory cells, chondroid and osseous metaplasia. Compared with the sham operated group, the oophrectomised group showed a lesser average maximum stress (42.9 N/m(2) versus 33.7 N/m(2)) at six weeks, which was significant (p < .05). Succeeding weeks showed no significant biomechanical differences between the two groups. The sham operated group showed greater inflammatory response, which was statistically significant (p < 0.05), and also revealed greater cell proliferation and density. The results of this study revealed that endogenous oestrogen may improve healing of the Achilles tendon in rats.

Comparison of the protective effects of melatonin and amifostine on radiation-induced epiphyseal injury.

PURPOSE: We compared the effects of amifostine and melatonin in preventing radiation-induced epiphyseal growth plate injury in rats. MATERIALS AND METHODS: Four-week-old (65-85 g), growing male Sprague-Dawley rats were randomly assigned to receive radiation alone, at 25 Gy in three fractions (group R), or this dose of fractionated radiation proceeded by prophylactic amifostine 200 mg/kg i.p. (group A), melatonin 15 mg/kg i.p. (group M), or amifostine + melatonin (group AM). The right rear extremity of each animal was irradiated while the contralateral leg was shielded from radiation, as a control. Bone growth based on the length of the tibia, femur, and overall limb was calculated 6 weeks after the treatment. RESULTS: In groups R, A, M, and AM, the mean growth loss (GL) for the overall limb was 56.9 +/- 8.1%, 46.8 +/- 7.7%, 36.6 +/- 4.3%, and 38.5 +/- 5.1%, respectively. The limb length discrepancies (LLD) in groups R, A, M, and AM were 13.8 +/- 1.4%, 10.5 +/- 0.3%, 7.4 +/- 0.7%, and 8.8 +/- 1.1%, respectively. Differences in LLD were significant between each treatment group and group R (range: p = 0.0001-0.001). Differences in either of mean GL and LLD were not significant between groups M and AM; however both of these groups had significantly less GL and LLD than group A. CONCLUSIONS: We observed a superior radioprotective function of melatonin over amifostine in preventing radiation-induced epiphyseal growth plate injury, without any increase in radioprotective effect by adding amifostine to melatonin.