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).

Protective Effects of Curcumin Against Paclitaxel-Induced Spinal Cord and Sciatic Nerve Injuries in Rats.

Paclitaxel (PTX) is an antineoplastic agent commonly used in the treatment of solid tumors and is known to cause dose-limiting peripheral neurotoxicity. This study was performed to evaluate the protective effect of curcumin (CUR) against PTX-induced spinal cord and sciatic nerve injuries in rats. The rats were administered PTX (2 mg/kg, BW) intraperitoneally for the first 5 consecutive days followed by administration of CUR (100 and 200 mg/kg, BW daily in corn oil) orally for 10 days. Our results showed that CUR significantly reduced mRNA expression levels of NF-κB, TNF-α, IL-6, iNOS and GFAP whereas caused an increase in levels of Nrf2, HO-1 and NQO1 in the spinal cord and sciatic nerve of PTX-induced rats. In addition, CUR suppressed the activation of apoptotic and autophagic pathways by increasing Bcl-2 and Bcl-xL, and decreasing p53, caspase-3, Apaf-1, LC3A, LC3B and beclin-1 mRNA expression levels. The results showed that CUR also maintained the spinal cord and sciatic nerve histological architecture and integrity by both LFB staining and H&E staining. Immunohistochemical expressions of 8-OHdG, caspase-3 and LC3B in the PTX-induced spinal cord tissue were decreased after administration of CUR. Taken together, our findings demonstrated that CUR has protective effects on PTX-induced spinal cord and sciatic nerve injuries in rats.

Therapeutic efficacy of zingerone against vancomycin-induced oxidative stress, inflammation, apoptosis and aquaporin 1 permeability in rat kidney.

Vancomycin (VCM) is a glycopeptidic broad-spectrum antibiotic against methicillin-resistant Staphylococcus aureus, though it has some adverse effects, including nephrotoxicity, that limit its usefulness. Zingerone (ZO), a component of dry ginger root, has several pharmacological activities due to its antioxidant, anti-inflammatory and antiapoptotic properties. The aim of this study was to determine the therapeutic efficacy of ZO against VCM-induced oxidative stress, inflammation, apoptosis and kidney aquaporin 1 (AQP1) levels in rats. Intraperitoneal administration of VCM (200 mg/kg body weight) for seven days increased kidney lipid peroxidation and decreased antioxidant enzyme activities, including kidney superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). VCM increased serum creatinine and urea levels and induced histopathological changes while causing a decrease in AQP1 protein level. VCM also increased the levels of the inflammatory markers nuclear factor kappa B (NF-κB), B-cell lymphoma-3(Bcl-3), interleukin-1ß (IL-1ß), interleukin-33 (IL-33), tumor necrosis factor-α (TNF-α), prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS), myeloperoxidase (MPO) and cyclooxygenase-2 (COX-2). Moreover, it activated the apoptotic pathway by increasing the expression levels of p53, Bcl-2 associated X protein (Bax), cysteine aspartate specific protease-3 (caspase-3) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), which is a marker of oxidative DNA damage. Treatment with ZO (25 and 50 mg/kg body weight) at both doses prevented nephrotoxicity by ameliorating the histopathological alterations, oxidative stress, inflammation, apoptosis, oxidative DNA damage and renal AQP1 levels. The findings of the present study suggested that ZO attenuates VCM-induced nephrotoxicity.

Chemoprotective effects of curcumin on doxorubicin-induced nephrotoxicity in wistar rats: by modulating inflammatory cytokines, apoptosis, oxidative stress and oxidative DNA damage.

Doxorubicin (DXR) is one of the most important chemotherapeutic agent. However, nephrotoxicity reduces its clinical utility in humans. The aim of the study was to investigate protective effects of curcumin (CMN) against DXR-induced nephrotoxicity. Rats were subjected to oral treatment of CMN (100 and 200 mg/kg body weight) for 7 days. Nephrotoxicity was induced by single intra peritoneal injection of DXR (40 mg/kg body weight) on the fifth day and then the experiment was terminated on the eighth day. Nephroprotective effects of CMN were associated with decrease in serum toxicity markers and increase in antioxidant enzyme activities. CMN was able to reduced the levels of inflammatory markers such as TNF-α, NF-κB, IL-1ß, iNOS and COX-2 in the rats. It also reduced the expressions of apoptotic marker including caspase-3, and oxidative DNA damage marker including 8-OHdG. Collectively, these findings indicated that CMN protect against DXR-induced nephrotoxicity.

Curcumin ameliorates doxorubicin-induced cardiotoxicity by abrogation of inflammation, apoptosis, oxidative DNA damage, and protein oxidation in rats.

Doxorubicin (DXR) is a highly effective drug for chemotherapy. However, cardiotoxicity reduces its clinical utility in humans. The present study aimed to assess the ameliorative effect of curcumin against DXR-induced cardiotoxicity in rats. Rats were subjected to oral treatment of curcumin (100 and 200 mg/kg body weight) for 7 days. Cardiotoxicity was induced by single intraperitoneal injection of DXR (40 mg/kg body weight) on the 5th day and the rats sacrificed on 8th day. Curcumin ameliorated DXR-induced lipid peroxidation, glutathione depletion, decrease in antioxidant (superoxide dismutase, catalase, and glutathione peroxidase) enzyme activities, and cardiac toxicity markers (CK-MB, LDH, and cTn-I). Curcumin also attenuated activities of Caspase-3, cyclooxygenase-2, inducible nitric oxide synthase, and levels of nuclear factor kappa-B, tumor necrosis factor-α, and interleukin-1ß, and cardiac tissue damages that were induced by DXR. Moreover, curcumin decreased the expression of 8-OHdG and 3,3'-dityrosine. This study demonstrated that curcumin has a multi-cardioprotective effect due to its antioxidant, anti-inflammatory, and antiapoptotic properties.