Nigella sativa oil reduces oxidative/nitrosative stress in the salivary gland of rats exposed to total cranial irradiation

Patients with head and neck cancer who receive radiotherapy experience serious side-effects during and after their treatment. Radiotherapy affects the salivary glands, causing a change in the composition of the saliva and a decrease in its flow. In this study, we aimed to investigate whether Nigella sativa oil (NSO) has a possible protective effect in preventing the harmful effects of free radicals formed by radiotherapy in rats. Thirty-six male Wistar-Albino rats weighing 200 ± 20 g were used. The rats were randomly divided into four groups: control, sham, irradiation (IR), and IR plus NSO groups. Xanthine oxidase (XO), nitric oxide synthase (NOS) activities, nitric oxide (NO•), peroxynitrite (ONOO-), malondialdehyde (MDA) levels were determined in salivary tissue of rats. NOS, XO activities, NO•, ONOO-, and MDA values were found to be significantly higher in the irradiated rats only compared to all other groups. As a results, NSO reduces oxidative/nitrosative stress markers and has antioxidant effects, which also augments the antioxidant capacity in the salivary tissue of rats.

Caffeic acid phenethyl ester: A review on its pharmacological importance, and its association with free radicals, COVID-19, and radiotherapy

Caffeic acid phenethyl ester (CAPE), a main active component of propolis and a flavonoid, is one of the natural products that has attracted attention in recent years. CAPE, which has many properties such as anti-cancer, anti-inflammatory, antioxidant, antibacterial and anti-fungal, has shown many pharmacological potentials, including protective effects on multiple organs. Interestingly, molecular docking studies showed the possibility of binding of CAPE with replication enzyme. In addition, it was seen that in order to increase the binding security of the replication enzyme and CAPE, modifications can be made at three sites on the CAPE molecule, which leads to the possibility of the compound working more powerfully and usefully to prevent the proliferation of cancer cells and reduce its rate. Also, it was found that CAPE has an inhibitory effect against the main protease enzyme and may be effective in the treatment of SARS-CoV-2. This review covers in detail the importance of CAPE in alternative medicine, its pharmacological value, its potential as a cancer anti-proliferative agent, its dual role in radioprotection and radiosensitization, and its use against coronavirus disease 2019 (COVID-19).

Thymoquinone: A Review of Pharmacological Importance, Oxidative Stress, COVID-19, and Radiotherapy

Widely consumed worldwide, Nigella sativa (NS) is a medicinal herb commonly used in various alternative medicine systems such as Unani and Tibb, Ayurveda, and Siddha. Recommended for regular use in Tibb-e-Nabwi (Prophetic Medicine), NS is considered one of the most notable forms of healing medicine in Islamic literature. Thymoquinone (TQ), the main component of the essential oil of NS, has been reported to have many properties such as antioxidant, anti-inflammatory, antiviral, and antineoplastic. Its chemical structure indicates antiviral potential against many viruses, including the hepatitis C virus, human immunodeficiency virus, and other coronavirus diseases. Interestingly, molecular docking studies have demonstrated that TQ can potentially inhibit the development of the coronavirus disease 2019 (COVID-19) by binding to the receptor site on the transmembrane serine proteinase 2 (the activator enzyme that attaches the virus to the cell). In addition, TQ has been shown to be effective against cancer cells due to its inhibitory effect by binding to the different regions of MDM2, according to the proposed molecular docking study. Detailed in this review is the origin of TQ, its significance in alternative medicine, pharmacological value, potential as a cancer anti-proliferative agent, use against the coronavirus disease 2019 (COVID-19), and treatment of other diseases.

Moringa Oleifera: A Review of Its Occurrence, Pharmacological Importance and Oxidative Stress

Oxidative/nitrosative stress can be caused by excessive production of ROS and RNS with metabolic reactions that change the balance in favor of oxidants in cases where oxidants increase and antioxidants decrease in organisms using oxygen. ROS and RNS react with several biological macromolecules in cells, such as carbohydrates, nucleic acids, lipids, and proteins, and alter their functions. Some natural antioxidants are constantly being researched for their benefits in terms of human health, which can strengthen the body's antioxidant defense system and have the potential to scavenger free radicals. It is a well-known and practical strategy to prevent and / or treat diseases due to the consumption of more suitable fruits, herbs, spices and vegetables, and the presence of bioactive antioxidant compounds. Moringa oleifera, a new and important one of these plants, has a wide range of bioactive compounds that can be obtained in different herbal structures such as leaves, seeds, stems and shells. It consists of bioactive molecules, such as phenolic compounds, fats, fatty acids, carbohydrates, proteins, functional peptides, vitamins, minerals and essential amino acids as well as a number of glycosides and has great potential for use in various formulations in various health and food products. This review highlights the formation of MO, its importance in natural medicine, its pharmacological value, and its role as a possible anti-proliferative agent against cancer and its use in some diseases.

Caffeic Acid Phenethyl Ester-Incorporated Radio-Sensitive Nanoparticles of Phenylboronic Acid Pinacol Ester-Conjugated Hyaluronic Acid for Application in Radioprotection

We synthesized phenylboronic acid pinacol ester (PBPE)-conjugated hyaluronic acid (HA) via thiobis(ethylamine) (TbEA) linkage (abbreviated as HAsPBPE conjugates) to fabricate the radiosensitive delivery of caffeic acid phenetyl ester (CAPE) and for application in radioprotection. PBPE was primarily conjugated with TbEA and then PBPE-TbEA conjugates were conjugated again with hyaluronic acid using carbodiimide chemistry. CAPE-incorporated nanoparticles of HAsPBPE were fabricated by the nanoprecipitation method and then the organic solvent was removed by dialysis. CAPE-incorporated HAsPBPE nanoparticles have a small particle size of about 80 or 100 nm and they have a spherical shape. When CAPE-incorporated HAsPBPE nanoparticles were irradiated, nanoparticles became swelled or disintegrated and their morphologies were changed. Furthermore, the CAPE release rate from HAsPBPE nanoparticles were increased according to the radiation dose, indicating that CAPE-incorporated HAsPBPE nanoparticles have radio-sensitivity. CAPE and CAPE-incorporated HAsPBPE nanoparticles appropriately prevented radiation-induced cell death and suppressed intracellular accumulation of reactive oxygen species (ROS). CAPE and CAPE-incorporated HAsPBPE nanoparticles efficiently improved survivability of mice from radiation-induced death and reduced apoptotic cell death. We suggest that HAsPBPE nanoparticles are promising candidates for the radio-sensitive delivery of CAPE.