Radioprotective effect of thymoquinone on salivary gland of rats exposed to total cranial irradiation

Abstract

Results showed that thymoquinone reduces oxidative and nitrosative stress parameters and has antioxidant effects and a free radical scavenging activity.

Radiation-Induced Salivary Gland Dysfunction: Mechanisms, Therapeutics and Future Directions

“…Reactive oxygen species (ROS) production is a known consequence of IR treatment and typically induces cellular damage immediately following IR exposure. In rats receiving 5 Gy IR, there was a significant reduction in the activity of the free radical scavenging enzymes superoxide dismutase, glutathione peroxidase and glutathione S-transferase that correlates with elevated levels of the oxidative stress markers, malondialdehyde and xanthine oxidase, as well as increased levels of peroxynitrite, nitric oxide synthase and nitric oxide in salivary glands at day 10 post-IR [61]. In mouse primary submandibular gland (SMG) cells, mitochondrial ROS levels were increased by days 1-3 post-IR with a reduction in ROS levels observed in cells deficient in transient receptor potential melastatin-related 2 (TRPM2), a calcium-permeable cation channel that is activated by oxidative stress and the DNA damage responsive protein, poly (ADP-ribose) polymerase 1 (PARP1), which correlates with improved salivary secretory function post-IR [45].…”

“…Following irradiation, rodent models show decreased saliva flow at approximately 3 days and a loss of amylase secretion reported as early as 4 days in rats post-IR [2,56,58]. In the acute phase, immediate DNA damage [6,59], rapid apoptosis of acinar cells [4,6,58], and elevated levels of intracellular calcium [45,46] and reactive oxygen species [45,46,60,61] contribute to acute loss of glandular function following irradiation. This period is also marked by release of ATP, which activates the P2X7 receptor (P2X7R), and P2X7R-dependent release of prostaglandin E 2 (PGE 2 ) in murine parotid cells [48].…”

Thymoquinone (2-Isopropyl-5-methyl-1, 4-benzoquinone) as a chemopreventive/anticancer agent: Chemistry and biological effects

“…Thymoquinone (2-Isopropyl-5-methyl-1, 4-benzoquinone) is the bioactive constituent of the volatile oil of black cumin ( Nigella sativa L.) seeds that has been extensively utilised traditionally in Middle East and Southeast Asian countries owing to its various health promoting capacities (Majdalawieh et al, 2017). It has been widely analyzed for its broad range of medicinal and pharmacological activities including but not limited to anti-inflammatory (Taka et al, 2018), anti-oxidant (Armutcu et al, 2018), antihistaminic (Kanter et al, 2006), antitumor (Singh et al, 2018), analgesic (Amin and Hosseinzadeh, 2016), anti-Alzheimer’s (Cascella et al, 2018), hepatoprotective, neuroprotective (Noorbakhsh et al, 2018), renoprotective, histone protein modulator (Rasheed et al, 2018), insecticidal (Scott et al, 2017), anti-ischemic (Bouhlel et al, 2017), Leishmanicidal (Mahmoudvand et al, 2015), radioprotective effects (Akyuz et al, 2017). TQ has also been clinically tested for a diverse kind of ailments like arthritis, diabetes, hypercholesterolemia etc.…”

Evaluation of the radioprotective effects of thymoquinone on dynamic thiol-disulphide homeostasis during total-body irradiation in rats

“…Akyuz et al investigated the radioprotective effects of TQ against radiation-induced damage in the salivary glands of rats. They found that by reducing the formation of nitric oxide, peroxynitrite, and malondialdehyde, and decreasing xanthine oxidase and nitric oxide synthase activities, TQ had antioxidant effects and free radical scavenging activity [24]. Although these studies demonstrate the ability of TQ to reduce oxidative stress using oxidant and antioxidant parameters, none of them evaluated the effect of TQ on thiol/disulphide homeostasis.…”