The present study evaluated the neuroprotective and antioxidant effects of quercetin in a rat model of sciatic nerve crush injury using histopathological, morphometric and biochemical methods. A total of 48 male Sprague Dawley rats, aged 10-12 weeks old were randomly divided into eight groups, consisting of two sham groups (S‑7, S‑28), three quercetin‑treated groups (Q‑7, Q‑28; 200 mg/kg/7 days), trauma (T‑7, T‑28; 1 min sciatic nerve crush injury) and three trauma+quercetin groups (T+Q‑7, T+Q‑28; trauma+quercetin 200 mg/kg/7 days). Rats were sacrificed on day 7 or 28. Oxidant‑antioxidant biochemical parameters in nerve tissues from all groups were analyzed using histopathological staining with toluidine blue and Masson's trichrome. DNA fragmentations were identified using terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick‑end labeling in cells from each tissue sample. Degeneration of the axons and myelin sheath, the breakdown of the concentric lamellar structure of the myelin sheath and axonal swelling were observed in groups T‑7 and T‑28. Myelin sheath thicknesses, nerve fiber diameters and the number of myelinated nerve fibers decreased, while the apoptotic index (AI) increased in the T‑7 and T‑28 groups. However, it was observed that nerve regeneration began in the T+Q‑7 and T+Q‑28 groups compared with the sham groups, together with the healing of cellular damage and axonal structure and a decrease in the AI. Malondialdehyde and superoxide dismutase activity did not differ significantly between the T‑7 and S‑7 groups. However, catalase activity significantly decreased in the T‑28 group when compared with the sham 7 day group. Tissue malondialdehyde levels significantly increased, while serum catalase activity increased in the T+Q‑7 group compared with the T‑7 group. These results suggest that quercetin has beneficial effects on nerve regeneration and may shorten the healing period in crush‑type sciatic nerve injuries.

Cisplatin (CP) is a chemotherapeutic agent used to treat various types of cancer; nephrotoxicity is the most common adverse effect of the drug. We investigated the protective effects of propolis against CP induced kidney injury. Thirty-six male rats were divided into six equal groups: untreated control group, 50 mg/kg/day propolis group, 100 mg/kg/day propolis group, single-dose 7 mg/kg CP group, 7 mg/kg CP + 50 mg/kg/day propolis and 7 mg/kg CP + 100 mg/kg propolis. Rats were sacrificed after 14 days and kidneys were removed for histopathological and biochemical analyses. We used hematoxylin & eosin and periodic acid-Schiff staining to evaluate kidney histopathology and we used the TUNEL technique to assess apoptosis. We also measured total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), ischemia-modified albumin (IMA) and malondialdehyde (MDA) levels in tissue and blood specimens. Normal morphology was observed in the control, 50 mg/kg/day propolis and 100 mg/kg/day propolis groups by light microscopy. Degeneration of tubule cells, edema and tubule dilation were increased in the CP group compared to the control group. Degeneration of tubule cells and dilation of Bowman’s spaces were decreased in the CP + 50 mg/kg/day propolis and CP + 100 mg/kg/day propolis groups compared to the CP group. Tubule dilation decreased significantly in the CP + 100 mg/kg propolis group compared to the CP group. Also, the 7 mg/kg CP group exhibited altered proximal tubule epithelial cells, loss of brush border and thickening of the parietal layer of Bowman’s capsule in glomeruli and basal laminae of tubules. A normal brush border was observed in the CP + 50 mg/kg/day propolis and CP + 100 mg/kg/day groups. Serum OSI and MDA levels were increased in the CP group compared to the control group. Serum MDA levels decreased significantly in the CP + 50 mg/kg/day propolis and 100 mg/kg CP + propolis groups compared to the CP group. CP caused significant damage to kidney tissue; propolis exhibited dose-dependent prevention of tissue damage.

Purpose: To investigate the effect on male rat kidney and bladder tissues of exposure to 900-megahertz (MHz) electromagnetic field (EMF) applied on postnatal days 22–59, inclusive. Materials and methods: Twenty-four male Sprague Dawley rats, aged 21 days, were used. These were divided equally into one of three groups, control (CG), sham (SG) or EMF (EMFG). CG was not exposed to any procedure. SG rats were kept inside a cage, without being exposed to the effect of EMF, for 1 h a day on postnatal days 22–59, inclusive. EMFG rats were exposed to continuous 900-MHz EMF for 1 h a day under the same conditions as those for the SG rats. Rats were sacrificed on postnatal day 60, and the kidney and bladder tissues were removed. Tissues were stained with hematoxylin and eosin (H&E) and Masson trichrome for histomorphological evaluation. The TUNEL method was used to assess apoptosis. Transmission electron microscopy (TEM) was also used for the kidney tissue. Oxidant/antioxidant parameters were studied in terms of biochemical values. Results: The findings showed that tissue malondialdehyde increased in EMFG compared to CG and SG in both kidney (p = 0.004 and p = 0.004, respectively) and bladder tissue (p = 0.004, p = 0.006, respectively), while catalase and glutathione levels decreased compared to CG (p = 0.004; p = 0.004, respectively) and SG (p = 0.004; p = 0.004, respectively). In the EMF group, pathologies such as dilatation and vacuolization in the distal and proximal tubules, degeneration in glomeruli and an increase in cells tending to apoptosis were observed in kidney tissue. In bladder tissue, degeneration in the transitional epithelium and stromal irregularity and an increase in cells tending to apoptosis were observed in EMFG. Additionally, EMFG samples exhibited glomerular capillary degeneration with capillary basement membranes under TEM. Conclusions: We conclude that continuous exposure to the effect of 900-MHz EMF for 1 h a day on postnatal days 22–59, inclusive, causes an increase in oxidative stress and various pathological changes in male rat kidney and bladder tissues.

The purpose of this study was to reveal the combined effects of propolis (P) and quercetin (Q) against diabetic peripheral neuropathy developing with streptozotocin-induced diabetes in rats. Sixty-four adult male rats were divided into eight equal groups: control, P (100 mg/kg/day), Q (100 mg/kg/day), P + Q (100 mg/day for both), diabetes mellitus (DM) (single-dose 60 mg/kg streptozotocin), DM + P, DM + Q, and DM + P + Q. The rats were sacrificed, and blood and sciatic nerve tissues were collected. Blood glucose and malondialdehyde (MDA) levels increased, while IL-6 and total antioxidant status decreased in the DM group (p = 0.016 and p = 0.047, respectively). Ultrastructural findings showed degeneration of the axon and myelin sheath. The apoptotic index (AI %), TNF-α, and IL-1β immunopositivity increased significantly in the DM group (p < 0.001). Morphological structures approaching those of the controls were observed in the DM + P, DM + Q, and DM + P + Q groups. Morphometric measurements increased markedly in all treatment groups (p < 0.001), while blood glucose and MDA levels, AI (%), TNF-α, and IL-1β immunopositivity decreased. In conclusion, the combined effects of propolis and quercetin in diabetic neuropathy may provide optimal morphological protection with neuroprotective effects by reducing hyperglycemia, and these may represent a key alternative supplement in regenerative medicine.