Lycopene in the Prevention of Radiation-Induced Esophagitis

Lycopene protects against ionizing radiation-induced testicular damage by inhibition of apoptosis and mitochondrial dysfunction

Ionizing radiation (IR) is one of the key contributors that cause male infertility by disturbing spermatogenesis. Lycopene, a carotenoid with strong antioxidant properties, was shown to protect against oxidative damage induced by IR in several experimental models. The present study was designed to explore the possible protective effects of lycopene against IR-induced testicular damage in C57BL/6 mice. Mice were administered lycopene (20 mg/kg) by oral gavage for seven consecutive days prior to a single dose of whole-body X-ray irradiation (4 Gy, 1 Gy/min). We observed that lycopene remarkably augmented sperm motility and reduced sperm abnormalities in mice following IR exposure. Histopathological analyses also revealed that lycopene ameliorated the structural damage of seminiferous tubules and enhanced the regeneration of seminiferous epithelium following IR stress. Moreover, lycopene attenuated IR-induced oxidative stress, as evidenced by a decreasing lipid peroxidation level and an increase in the antioxidant enzyme superoxide dismutase activity. In addition, lycopene reduced the γH2AX expression and the number of TUNEL-positive cells in the germinal epithelium, as well as restoring the imbalance of Bax/Bcl-2 expression induced by IR exposure. Furthermore, lycopene prevented mitochondrial membrane potential depolarization and ATP reduction and preserved the activities of mitochondrial complexes I-IV in the testes of mice after exposure to IR. Lycopene also improved mitochondrial biogenesis in testes of mice exposed to IR, presenting as restored expressions of PGC-1α, Nrf1, and Tfam. Taken together, our results suggest that lycopene alleviates IR-induced testicular damage, and the underlying mechanism involves at least in part the inhibition of the mitochondrial apoptotic pathway and the maintenance of mitochondrial respiration and biogenesis. The beneficial effect of lycopene highlights the therapeutic potential of this plant-derived antioxidant against impaired spermatogenesis and male infertility induced by IR.

Metabolic Profiling Implicates a Critical Role of Cyclooxygenase-2-Mediated Arachidonic Acid Metabolism in Radiation-Induced Esophageal Injury in Rats

Radiation-induced esophageal injury (RIEL) is a major dose-limiting complication of radiotherapy, especially for esophageal and thoracic cancers. RIEL is a multi-factorial and multi-step process, which is regulated by a complex network of DNA, RNA, protein and metabolite. However, it is unclear which esophageal metabolites are altered by ionizing radiation and how these changes affect RIEL progression. In this work, we established a rat model of RIEL with 0-40 Gy X-ray irradiation. Esophageal irradiation using ≥25 Gy induced significant changes to rats, such as body weight, food intake, water intake and esophageal structure. The metabolic changes and related pathways of rat esophageal metabolites were investigated by liquid chromatography-mass spectrometry (LC-MS). One hundred eighty metabolites showed an up-regulation in a dose-dependent manner (35 Gy ≥ 25 Gy > controls), and 199 metabolites were downregulated with increasing radiation dose (35 Gy ≤ 25 Gy < controls). The KEGG analysis showed that ionizing radiation seriously disrupted multiple metabolic pathways, and arachidonic acid metabolism was the most significantly enriched pathway. 20 metabolites were dysregulated in arachidonic acid metabolism, including up-regulation of five prostaglandins (PGA2, PGJ2, PGD2, PGH2, and PGI2) in 25 or 35 Gy groups. Cyclooxygenase-2 (COX-2), the key enzyme in catalyzing the biosynthesis of prostaglandins from arachidonic acid, was highly expressed in the esophagus of irradiated rats. Additionally, receiver operating characteristic (ROC) curve analysis revealed that PGJ2 may serve as a promising tissue biomarker for RIEL diagnosis. Taken together, these findings indicate that ionizing radiation induces esophageal metabolic alterations, which advance our understanding of the pathophysiology of RIEL from the perspective of metabolism.

Protective effect of lycopene on oral mucositis and antioxidant capacity of blood plasma in the rat exposed to gamma radiation

Background:

Nowadays, radiotherapy is used effectively for the treatment of head and neck cancers. Mucositis is one of the most important side effects of radiotherapy. Radio-protective agents protect tissues and cells against the adverse effects due to ionizing radiation and cleave radiation-induced free radicals. Lycopene as a potent antioxidant protects cells against oxidative damage by free radical–scavenging. The present study investigated the antioxidant effect of lycopene on oral mucosa of irradiated rats.

Methods:

In this experimental animal study, 28 rats were placed in four groups as follows: treated with 50 mg /kg of lycopene (L50), solvent+irradiation (SR), 25 mg / kg of lycopene+irradiation (LR25), and 50 mg / kg of lycopene+irradiation (LR50). The rats received lycopene intraperitoneally. On the irradiation day (day 0) and tenth day of radiation, blood samples were taken from the animals for FRAP and TBARS tests.

Results:

The results showed that the LR50 group did not show mucositis higher than grade 2. There was a significant difference (p<0.05) between SR and the L50 regarding the severity of mucositis. In addition, L50 showed higher antioxidant activity and lower peroxidation than SR.

Conclusion:

Lycopene reduced the severity of mucositis. Therefore, it can be used as a potential and promising nutritional substance to prevent radiotherapy complications, especially in the treatment of head and neck cancers. However, further research is necessary to confirm these results.

The Power of Phytochemicals Combination in Cancer Chemoprevention

Conventional therapies for cancer treatment have posed many challenges, including toxicity, multidrug resistance and economic expenses. In contrast, complementary alternative medicine (CAM), employing phytochemicals have recently received increased attention owing to their capability to modulate a myriad of molecular mechanisms with a less toxic effect. Increasing evidence from preclinical and clinical studies suggest that phytochemicals can favorably modulate several signaling pathways involved in cancer development and progression. Combinations of phytochemicals promote cell death, inhibit cell proliferation and invasion, sensitize cancerous cells, and boost the immune system, thus making them striking alternatives in cancer therapy. We previously investigated the effect of six phytochemicals (Indol-3-Carbinol, Resveratrol, C-phycocyanin, Isoflavone, Curcumin and Quercetin), at their bioavailable levels on breast cancer cell lines and were compared to primary cell lines over a period of 6 days. This study showed the compounds had a synergestic effect in inhibiting cell proliferation, reducing cellular migration and invasion, inducing both cell cycle arrest and apoptosis. Despite the vast number of basic science and preclinical cancer studies involving phytochemicals, the number of CAM clinical trials in cancer treatment still remains nascent. In this review, we summarize findings from preclinical and clinical studies, including our work involving use of phytochemicals, individually as well as in combination and further discuss the potential of these phytochemicals to pave way to integrate CAM in primary health care.

Therapeutic effects of Co-Venenum Bufonis Oral Liquid on radiation-induced esophagitis in rats

To investigate the effects of Co-Venenum Bufonis Oral Liquid (cVBOL) on radiation-induced esophagitis in rats. Irradiation (30 Gy) with X-RAD 225 x-ray was applied to induce esophagitis in 64 Wistar rats and treated by different methods. The body weight of rats either in RT group, cVBOL+RT, or EM+RT group was significantly decreased when compared with that in normal group (P<0.0001). After irradiation, histopathological studies, immunohistochemistry, and MRI scanning on esophagus were performed. Serum TNF-α,IL-6 and IL-10 were also determined by ELISA at 7, 14, 21 and 28 days after radiation treatment. The results demonstrated that radiation caused esophageal injury and thickening of esophageal tissue layers. The esophageal tissues after radiation treatment showed typical pathological changes of esophagitis. Radiation also caused esophagus edema. Treatment of cVBOL reduced the severity of histological esophageal lesion, decreased the expression of bFGF and TGF-β1, and lowered serum levels of inflammatory cytokines including TNF-α, IL-6 and IL-10 over 28 days after radiation treatment. In conclusion, cVBOL treatment is effective to prevent radiation induced esophagitis and reduces radiation induced esophagitis may be mediated through its ant-inflammatory effects.

The protective role of jervine against radiation-induced gastrointestinal toxicity

In this study, we investigated whether jervine (J) could prevent gastrointestinal (GI) side effects of abdominopelvic radiotherapy (RT) in Wistar-Albino female rats. Rats were divided into five groups: control (C), J only (J), J administered at 5 mg/kg/days for 7 days, RT only (RT), J before RT (J + RT), J administered for seven days before RT, J both before and after RT (J + RT + J), and J administered for 7 days before RT and after RT for 3 days. The weights of rats were measured on the 1st, 7th, and 10th days of the study. Rats were sacrificed to obtain tissues from the liver and intestine, which was followed by taking blood samples intracardially. In addition, the tissues were stained with pyruvate dehydrogenase (PDH) immunohistochemically. In our study, J supplementation markedly reduced weight loss, and histopathological, immunohistochemical, biochemical results suggest that J had a protective effect on GI toxicity following RT.

Therapeutic effect of dental pulp stem cell transplantation on a rat model of radioactivity-induced esophageal injury

Dental pulp stem cell (DPSC) transplantation has been demonstrated to promote the regeneration and repair of tissues and organs and is a potentially effective treatment for radioactive esophageal injury. In this study, to explore the therapeutic effects of DPSCs on acute radiation-induced esophageal injury, DPSCs were cultured and transplanted into rats with acute radioactive esophageal injuries induced by radioactive ¹²⁵I seeds in vivo. In the injured esophagus, PKH26-labeled DPSCs co-localized with PCNA, CK14, CD71, and integrin α6, and the expression levels of these four makers of esophageal stem cells were significantly increased. After DPSC transplantation, the injured esophagus exhibited a greater thickness. In addition, the esophageal function and inflammation recovered faster. The results demonstrated that transplanted DPSCs, which trans-differentiated into esophageal stem cells in vivo, could repair the damaged esophageal tissue.