No abstract

Melatonin is an indoleamine with potent multifunctional biological and pharmacological effects, both receptor dependent and receptor-independent effects, including antioxidant, anticancer, antitumor, anti-inflammatory, anti-aging, anti-diabetic, antiviral, neuroprotective activities. Melatonin mitigates tissue injury via modification of abnormalities in redox status and other biochemical markers. At the molecular level, the biological and pharmacological activities of melatonin are attributed to the inhibition of nuclear factor-κappa beta (NF-κβ), c-Fos over expression and down-regulation of matrix metalloproteinases-3 (MMP-3), which are regulators of pro-inflammatory and pro-fibrotic cytokines. There are numerous scientific reports on the therapeutic potential of melatonin in treatment of asthma, respiratory diseases for infections, chronic obstructive pulmonary disease, lung cancer, pleural cavity diseases, as well as vascular pulmonary disease. In the present communication, we systematically review the therapeutic potential of melatonin in the treatment of respiratory diseases along with its molecular mechanism of actions.

The objective of this study was to evaluate the antioxidant effects of propolis, caffeic acid phenethyl ester (CAPE; active compound in propolis), and pollen on biochemical oxidative stress biomarkers in rat kidney tissue inhibited by N -nitro-L-arginine methyl ester (L-NAME). The biomarkers evaluated were paraoxonase (PON1), oxidative stress index (OSI), total antioxidant status (TAS), total oxidant status (TOS), asymmetric dimethylarginine (ADMA), and nuclear factor kappa B (NF-κB). TAS levels and PON1 activity were significantly decreased in kidney tissue samples in the L-NAME-treated group (P < 0.05). The levels of TAS and PONI were higher in the L-NAME plus propolis, CAPE, and pollen groups compared with the L-NAME-treated group. TOS, ADMA, and NF-κB levels were significantly increased in the kidney tissue samples of the L-NAME-treated group (P < 0.05). However, these parameters were significantly lower in the L-NAME plus propolis, CAPE, and pollen groups (P < 0.05) compared with rats administered L-NAME alone (P < 0.05). Furthermore, the binding energy of CAPE within catalytic domain of glutathione reductase (GR) enzyme as well as its inhibitory mechanism was determined using molecular modeling approaches. In conclusion, experimental and theoretical data suggested that oxidative alterations occurring in the kidney tissue of chronic hypertensive rats may be prevented via active compound of propolis, CAPE administration.

The aim of this study was to determine the effects of thymoquinone (TQ), which is the most essential active compound of Nigella sativa, on the spermatological parameters of ram semen during cryopreservation. Ejaculates were collected from five Sonmez rams using an artificial vagina and extended with Tris‐based extender not containing TQ (control, 0 μg/ml TQ) and containing 10, 25, 50 and 100 μg/ml TQ. The extended semen samples were equilibrated in a + 4°C cold cabinet for 2 h. After 2 h, the samples were loaded into 0.25 ml French straws. The straws were frozen by liquid nitrogen vapour and stored in a liquid nitrogen container (−196°C). The frozen straws were thawed in a water bath (37°C for 30 s) and evaluated in terms of motility characteristics, plasma membrane and acrosome integrity, mitochondrial reactive oxygen species levels, lipid peroxidation levels, DNA damage and biochemical alterations (oxidative stress index, malondialdehyde and glutathione). TQ100 had higher total motility (53.59 ± 3.01) and progressive motility (19.84 ± 1.44; not significantly different from TQ25 and TQ50) compared to the control and TQ10 (p ˂ 0.05). According to the results of the analyses on motility characteristics, there were significant differences between the groups in terms of curvilinear velocity (VCL), amplitude of lateral head displacement (ALH) and linearity (LIN; p ˂ 0.05). The highest DNA damage was detected in the control group (p ˂ 0.05). TQ50 had higher plasma membrane and acrosome integrity (59.56 ± 5.92) compared to the control and TQ25 (p < 0.05) but not significantly different from TQ10 and TQ100. The lowest mitochondrial reactive oxygen species levels were detected in TQ50 and TQ100 (p ˂ 0.05). There were no significant differences among the groups in terms of their oxidative stress index, lipid peroxidation, malondialdehyde and glutathione levels (p > 0.05). According to the results, it could be concluded that supplementing 50 or 100 μg/ml TQ to Tris extenders that were used for ram semen cryopreservation showed a positive effect on motility, plasma membrane integrity and acrosome integrity, and it reduced DNA damage and mitochondrial reactive oxygen species levels.

Nitric oxide (NO), produced by endothelial NO synthase, is recognised as a central antiinflammatory and antiatherogenic principle in the vasculature. Epidemiological and clinical studies have demonstrated that a growing list of natural products, as components of the daily diet or phytomedical preparations, may improve vascular function by enhancing NO bioavailability. In this article, we investigated antioxidant effects of propolis on biochemical parameters in kidney and heart tissues of acute NO synthase inhibited rats by Nω-nitro-l-arginine methyl ester (l-NAME). There was increase (p < 0.001) in the activities of catalase and malondialdehyde levels in the l-NAME treatment groups when compared with control rats, but NO levels were decreased in both kidney and heart tissues. There were statistically significant changes (p < 0.001) in these parameters of l-NAME + propolis treated rats as compared with l-NAME-treated group. In summary, propolis may influence endothelial NO production.

No abstract

We conducted this study to determine the potential cryopreservative effects of different hesperidin (vitamin P; H) doses on ram semen after freeze-thawing. Semen samples were obtained from Sönmez rams using an artificial vagina. The samples were divided into six groups: control, 10, 50, 100, 250, and 500 µg/mL H (C, H10, H50, H100, H250, and H500, respectively). At the end of the study, sperm motility and kinetic parameters, acrosome integrity (AI), mitochondrial membrane potential (MMP), viability, lipid peroxidation levels (LPL), chromatin damage, oxidant parameters, and antioxidant parameters were assayed. None of the doses of H added to the semen extender showed any enhancing effects on progressive motility compared to C (p > 0.05). In fact, H500 had negative effects (p < 0.05). Moreover, AI was the highest at the H10 dose, while LPL values were the lowest at the same dose (p < 0.05). The doses of H10 and H50 added to the Tris extender medium showed positive effects on sperm cell chromatin damage. Consequently, we can say that H doses used in this study are not effective on semen progressive motility, but the H10 dose is effective on AI and chromatin damage by reducing LPL.

In this study, the cryoprotective effect of different doses of propolis (P) on bull semen, which has strong pharmacological properties thanks to its rich phenolic components, was investigated biochemically and physiologically. Semen samples were collected from Simmental breed bulls via the artificial vagina and pooled. After dividing into five groups, control (C: no additive), and four different dose P (200, 100, 50, and 25 μg/mL) groups, the final concentration was diluted to 16×106 per straw. Semen samples were equilibrated at 4°C for approximately 4 hours, then placed in French straws and frozen. After thawing, sperm motility and kinetic parameters, DNA integrity by single-cell gel electrophoresis, sperm abnormalities by liquid fixation, and lipid peroxidation levels by the colorimetric method was analyzed by Computer-Assisted Semen Analyzer. P added to the diluent showed no effect on motility and kinetic parameters at P25 and P50 (p &gt;0.05), while P100 and P200 had a negative effect (p &lt;0.001). The addition of P (25 and 50) had a treatment effect on tail abnormality compared to C (p &lt;0.05). Especially P50 had a positive effect on tail length, tail DNA, and tail moment, while P100 and P200 caused DNA damage (p &lt;0.001). MDA levels increased in all P dose groups compared to C (p &lt;0.001). This study has clearly demonstrated that P25 and P50 supplements could be used therapeutically in the treatment of sperm abnormalities and prevention of DNA damage in post-thawed bull sperm.