Aysel Kükner

Dietary vitamin C and E modulates oxidative stress induced-kidney and lens injury in diabetic aged male rats through modulating glucose homeostasis and antioxidant systems.

Diabetes induces oxidative stress in aged human and rat, although daily supplementation of vitamins C and E (VCE) can be beneficial to aged diabetic rats by reducing free radical production. The aim of the present study was to evaluate whether dietary VCE supplementation relieves oxidative stress in streptozotocin (STZ)‐induced diabetic in aged rats. Thirty aged rats were randomly divided into three groups. The first group was used as a control. The second group was made diabetic using a single dose of intraperitoneal STZ. VCE‐supplemented feed was given to aged diabetic rats constituting the third group. On the 21st day of the experiment, blood, lens and kidney samples were taken from all animals. Glutathione peroxidase (GSH‐Px) activity in lens and kidney, reduced glutathione (GSH), vitamin E and β‐carotene concentrations in kidney were lower in the diabetic group than in the control whereas plasma glucose, urea and creatinine, and kidney and lens peroxidation (LP) levels were higher in the diabetic group than in the control. However, kidney and lens LP levels, and plasma glucose, urea and creatinine values were decreased by VCE supplementation. Lens and kidney GSH‐Px activity, kidney GSH, vitamin E and β‐carotene concentrations and erythrocyte counts were increased by VCE treatment. Kidney weights, vitamin A, haemoglobin, hematocrit, leukocyte and platelets values were not changed by diabetes and/or VCE supplementation. VCE ameliorated also diabetes‐induced histopathological changes in kidney. In conclusion, we observed that VCE supplementation is beneficial towards kidney and lens of aged diabetic rats by modulating oxidative and antioxidant systems. Copyright

Effect of platelet-rich plasma on tendon-to-bone healing after rotator cuff repair in rats: an in vivo experimental study

OBJECTIVE The purpose of this experimental study was to analyze the effects of local autologous platelet-rich plasma (PRP) injection on tendon-to-bone healing in a rotator cuff repair model in rats. METHODS Rotator cuff injury was created in 68 left shoulders of rats. PRP was obtained from the blood of an additional 15 rats. The 68 rats were divided into 4 groups with 17 rats in each group; PRP group (Week 2), control group (Week 2), PRP group (Week 4), and control group (Week 4). Platelet-rich plasma or saline was injected to the repair area intraoperatively. Rats were sacrificed 2 and 4 weeks after the surgery. Histological analysis using a semiquantitative scoring was performed on 7 rats per group. Tendon integrity and increases in vascularity and inflammatory cells and the degree of new bone formation were evaluated and compared between the groups. The remaining tendons (n=10) were mechanically tested. RESULTS Degree of inflammation and vascularity were less in the study group at both time intervals (p<0.05). Tendon continuity was better in the study group at 2 weeks (p<0.05). Obvious new bone formation was detected in the control group at 4 weeks (p<0.05). Biomechanically, platelet-rich plasma-treated specimens were stronger at 2 weeks (p<0.05). CONCLUSION Local autologous PRP injection may have beneficial effects on initial rotator cuff tendon-to-bone healing and enhance initial tendon-to-bone healing remodeling. This may represent a clinically important improvement in rotator cuff repair.

Does platelet-rich plasma enhance microfracture treatment for chronic focal chondral defects? An in-vivo study performed in a rat model

OBJECTIVE The purpose of the present study was to compare the effectiveness of platelet-rich plasma (PRP) + microfracture and microfracture treatments in the healing of chronic focal chondral defects. METHODS The study included 57 adult male Sprague-Dawley rats. Forty-two rats were divided into three groups of 14 rats with a chondral defect (control, microfracture only, PRP+microfracture). The remaining 15 rats were used to produce the PRP preparation. The rats were then euthanatized at 3 and 6 weeks after treatment and examined. Histological analysis using the modified Pineda scoring system and immunohistochemical staining for Type 2 collagen were performed. RESULTS At both time intervals, control group histological scores (Week 3: 8.8±1.2, Week 6: 8.5±0.7) were higher than microfracture (Week 3: 6.8±1.0, Week 6: 7.1±0.6) and PRP+microfracture (Week 3: 6.4±1.3, Week 6: 5.7±1.2) scores (p<0.05). The microfracture group score was higher at Week 6 than the PRP+microfracture group (p<0.05). The degree of Type 2 collagen staining was higher at Week 6 in the PRP+microfracture group and was unique in showing staining at the cell membrane. CONCLUSION The addition of PRP application to microfracture treatment appears to enhance cartilage healing in chronic focal chondral defects.

The effect of pinealectomy and leptin hormone on the proliferation and apoptosis activation in Syrian hamster testis in different photoperiods

The effects of pinealectomy and leptin hormone on proliferative and apoptotic processes in the epithelia of testicular seminiferous tubules of Syrian hamsters have been investigated. Proliferative and apoptotic processes were assessed semi-quantitatively by proliferating cell nuclear antigen (PCNA) and caspase-3 immune stainings. Animals used in the study were divided into four groups; control, pinealectomy (PinX), leptin-treated (10 microg/mL/day/kg body weight, intraperitoneally) and pinealectomy + leptin groups. Half of the hamsters in each group were exposed to short and the other half to long photoperiods for 8 weeks. In short photoperiod, PCNA activity especially in spermatogonia was significantly higher in the pinealectomy and leptin-treated groups compared with the control group. Histological score (HSCORE) value of PCNA in the PinX + leptin group was lower than those of PinX and leptin-treated groups. HSCORE value of caspase-3 in PinX and PinX + leptin groups was increased. In the long photoperiod, PCNA activation in the PinX group was significantly lower than the control group while the differences between the controls and other groups were not significant. The difference between the increases in caspase-3 activity in the PinX and control groups was significant. Thus, it was observed that photoperiods had no effect on the proliferation activity in the control groups. The inhibiting effect of short photoperiod on testis was not observed throughout 8 weeks. PinX eliminated the inhibiting effect of short photoperiod but did not alter the stimulating effect of long photoperiod. Leptin did not show any effect in long photoperiod but decreased proliferation by stimulating melatonin in short photoperiod.

Comparison of ocular surface side effects of topical travoprost and bimatoprost.

Purpose: To compare the subjective symptoms, conjunctival hyperemia, tearing response and conjunctival cytological changes secondary to topical administration of bimatoprost and travoprost for 6 months. Methods: Newly diagnosed primary open-angle glaucoma patients were randomly prescribed bimatoprost (35 cases) or travoprost (42 cases). Two patients in each group were excluded because they did not appear at their appointments regularly. Thus, 33 and 40 patients completed the study in the bimatoprost and travoprost groups, respectively. Redness, itching, foreign-body sensation, pain and discomfort were assessed by a questionnaire, and patients were examined for conjunctival hyperemia. Schirmer’s I and break-up time tests were performed, and impression cytology of conjunctiva was evaluated. Results: Subjective symptoms were similar in both groups. The only subjective symptom that changed significantly was redness. The change in conjunctival hyperemia along the study period correlated with the patient-reported redness in both groups, being highest on day 30. Schirmer’s test I and break-up time did not change with time and were similar in both groups. The impression cytology grade increased with time in both groups with the only significant difference between groups on day 90 (higher in the bimatoprost group). Conclusion: We observed conjunctival hyperemia as the most common side effect of bimatoprost and travoprost. Tear film functions were not affected by these drugs while cytological alterations were.

Effect of sirolimus on renal injury induced by bile duct ligation in rats

PURPOSE To evaluate the effects of sirolimus (SRL) on renal injury in rats with bile duct ligation. METHODS A total of 21 male Sprague-Dawley rats weighing 220-260 g were used. Group 1 (Sham-control, n=7) rats were undergone laparotomy alone and bile duct was just dissected from the surrounding tissue. Group 2 rats (BDL/Untreated, n=7) were subjected to bile duct ligation and no drug was applied. Group 3 rats (BDL/SRL, n =7) received a daily dose of sirolimus (0.5 mg·day(-1) x kg(-1) dissolved 1 ml in saline) by orogastric tube for 14 days after BDL. At the end of the two-week period, biochemical and histological evaluation were processed. RESULTS AST, ALT, AP and TB levels values were decreased in group 3 when compared to group 2. There was no significant difference in serum levels of BUN and creatinine among all the experimental groups. Histological evaluation of the liver of BDL/Untreated group rats demonstrated marked portal fibrosis and signs of major bile duct obstruction with prominent portal and lobular inflammation. In BDL/SRL group, moderate damage was seen. Tubular injury scores were higher in the BDL subgroups; however, group 3 rats showed considerably fewer lesions in the tubules and interstitium compared to the group 2 rats. In group 2 animals, in the epithelial cells of proximal tubules presented vacuoles and hydropic changes, atrophy and inflammatory cell infiltrate in the medullar interstitium. CONCLUSIONS Sirolimus decreased tubulointerstitial lesions in kidney induced by bile duct ligation in rats. The improve effects of sirolimus on renal morphology can be due to improved liver function or due to direct action on the kidney.

Effect of heparin on inflammation: An animal model of tracheal stents

The objective of this study was to investigate the effect of systemic heparin on tracheal and wound healing.

Protective Effects of CAPE on Liver Injury Induced by CCL4: An Electron Microscopy Study

This study was designed to investigate the protective effects of caffeic acid phenethyl ester on carbon tetrachloride-induced liver damage in rats. Twenty-four male Wistar rats were divided in three groups. Group I was used as control. Rats in group II were injected with carbon tetrachloride every other day for 1 month, whereas rats in group III were injected with carbon tetrachloride and caffeic acid phenethyl ester every other day for 1 month. At the end of the experiment, all animals were killed by decapitation and their livers were removed. Liver tissues were processed for electron microscopy. Histopathologically, hepatocytes of rats treated with carbon tetrachloride had damage in the cytoplasmic organelles and nuclei membranes as well as an excessive lipid accumulation in the hepatocytes. However, those histopathological changes were reduced with the coadministration of carbon tetrachloride and caffeic acid phenethyl ester. We conclude that caffeic acid phenethyl ester treatment has the capability to prevent carbon tetrachloride-induced liver damage in rats.

The Effects of Triiodothyronine on Rat Testis: A Morphometric and Immunohistochemical Study

The aim of present study was to investigate the effects of 3,3′,5-triiodothyronine (T3) on rat testis both morphometrically and immunohistochemically with determining of insulin-like growth factor I (IGF-I) expression. Adult male Wistar-albino rats used in the study were divided into two groups; control and T3-treated groups. After T3 treatment there was observed to be a decrease in testicular weights, diameters of seminiferous tubules and the number of sertoli cells, and an increase in the number of leydig cells (P<0.05). Some of the seminiferous tubule lumens of T3 administrated rats had cellular debris. IGF-I was localized in sertoli cells, late spermatids and leydig cells of all groups. IGF-I immunoreactivity in T3 treated rats was higher than in controls in all stages of the cycle of rat seminiferous epithelium, but the staining intensity of leydig cells were similar in both groups. In conclusion, the present results suggest that T3 may modulate the testicular function by affecting IGF-I activity at the gonadal level.

Vasoactive Intestinal peptide modulates c-Fos activity in the trigeminal nucleus and dura mater mast cells in sympathectomized rats.

Neurogenic inflammation in the dura mater caused by trigeminal nociceptive activation has been implicated in the pathophysiology of migraine. Vasoactive intestinal polypeptide (VIP) is a powerful neuroprotective neuropeptide that can modulate mast cell behavior. Migraine is also associated with sympathetic insufficiency. This study investigates the effects of VIP on the number of mast cells in the dura mater and on c‐Fos expression in the trigeminal nucleus of sympathectomized rats. Experiments were carried out with 32 Sprague‐Dawley male rats with body weights of 200–250 g. In the sympathectomized group, the left superior cervical sympathetic ganglion was removed. In the sympathectomized + VIP group, postoperative VIP 25 ng/kg/day (0.2 ml) was administered for 5 days. In the sham group, the ganglion and nerves were exposed but not dissected. Dura maters were stained with toluidine blue, and brainstems were labeled by indirect immunohistochemistry for c‐Fos. Sympathectomy significantly increased the number of mast cells in both the ipsilateral and the contralateral dura mater (P < 0.001). VIP decreased the number of mast cells in both sides of the dura mater in sympathectomized rats. VIP also decreased c‐Fos expression in the ipsilateral trigeminal nucleus of sympathectomized rats (P < 0.001). In the context of an experimental superior cervical ganglionectomy model of migraine, VIP is an efficient modulator of neurogenic inflammation of the dura.