Lycopene and Chemotherapy Toxicity

Lycopene alleviates 5-fluorouracil-induced nephrotoxicity by modulating PPAR-γ, Nrf2/HO-1, and NF-κB/TNF-α/IL-6 signals

5-Fluorouracil (5-FU) is one of the most used anticancer drugs. However, its nephrotoxicity-associated drawback is of clinical concern. Lycopene (LYC) is a red carotenoid with remarkable anti-inflammatory and anti-oxidative properties. In this study, rats were divided randomly into five groups: control, lycopene (10 mg) (10 mg/kg/day; P.O), 5-FU (30 mg/kg/day; i.p.), Lycopene (5 mg) + 5-FU (5 mg/kg + 30 mg/kg/day), and lycopene (10 mg) + 5-FU (10 mg/kg + 30 mg/kg/day). LYC attenuated the loss of renal function induced by 5-FU in a dose-dependent manner. Rats co-treated with LYC had lower serum urea, creatinine, uric acid and KIM-1 levels, and a higher serum albumin level than those receiving 5-FU alone. Furthermore, co-treatment with the high dose of LYC maintained renal oxidant-antioxidant balance by ameliorating/preventing the loss of antioxidants and the elevation of malondialdehyde. Rats treated with 5-FU had markedly lower renal levels of PPAR-gamma, HO-1, Nfr2, and Il-10 and higher levels of NF-kB, TNF-alpha, and IL6 compared to the control rats. Co-treatment with LYC attenuated the reduction in PPAR-gamma, HO-1, Nfr2, and IL-10 levels and moderated the elevated levels of NF-kB, TNF-alpha, and IL-6. The kidneys from rats co-treated with lycopene (10 mg) + 5-FU did not show the degenerative changes in the glomerular tufts and tubules observed for the rats treated with 5-FU alone. In conclusion, LYC is a promising therapeutic strategy for attenuating 5-FU-induced nephrotoxicity through the restoration of antioxidant activities and inhibition of inflammatory responses by modulating PPAR-γ, Nrf2/HO-1, and NF-κB/TNF-α/IL-6, signals.

The therapeutic potential of 1, 25-dihydroxy vitamin D3 on cisplatin-affected neurological functions is associated with the regulation of oxidative stress and inflammatory markers as well as levels of MMP2/9

Calcitriol as a biologically active form of vitamin D3 has beneficial effects on all body systems. This vitamin has a potent neuroprotective effect via several independent mechanisms against brain insults induced by anticancer drugs. The present study was designed to examine the neuroprotective effects of calcitriol against neurotoxicity induced by cisplatin. Induction of neurotoxicity was done with cisplatin administration (5 mg/kg/week) for 5 successive weeks in male Wistar rats. The neuroprotective influence of calcitriol supplementation (100ng/kg/day for 5 weeks) was assessed through behavioral, electrophysiological, and molecular experiments. Cisplatin administration impaired spatial learning and memory and decreased prefrontal brain-derived neurotrophic factor (BDNF). Peripheral sensory neuropathy was induced through cisplatin administration. Cisplatin also reduced the amplitudes of the compound action potential of sensory nerves in electrophysiological studies. Cisplatin treatment elevated MDA levels and reduced anti-oxidant (SOD and GPx) enzymes. Pro-inflammatory cytokines (IL-1β and TNF-α) and metalloproteinase-2 and 9 (MMP-2/9) were augmented through treatment with cisplatin. Learning and memory impairments along with BDNF changes caused by cisplatin were amended with calcitriol supplementation. Reduced sensory nerve conduction velocity in the cisplatin-treated group was improved by calcitriol. Calcitriol partially improved redox imbalance and diminished the pro-inflammatory cytokines and MMP-2/9 levels. Our findings showed that calcitriol supplementation can relieve cisplatin-induced peripheral neurotoxicity. Calcitriol can be regarded as a promising new neuroprotective agent.

Association between tomato consumption and blood pressure in an older population at high cardiovascular risk: observational analysis of PREDIMED trial

AIMS

Clinical studies have produced conflicting evidence on the effects of the consumption of tomatoes on blood pressure, and there are limited data from epidemiologic studies. This study assesses whether tomato consumption (Solanum lycopersicum L.) is associated with systolic and diastolic blood pressure, and the risk of hypertension in a prospective 3-year longitudinal study in older adults at high cardiovascular risk.

METHODS AND RESULTS

The present study was carried out within the PREDIMED (Prevención con Dieta Mediterránea) trial involving 7056 (82.5% hypertensive) participants. The consumption of tomato (g/day) was measured using a validated Food Frequency Questionnaire and categorized into four groups: lowest (<44 g), intermediate (44-82 g), upper-intermediate (82-110 g), and highest (>110 g). Multilevel linear mixed models examined blood pressure and tomato consumption association. Cox proportional-hazards models analysed hypertension risk in 1097 non-hypertensive participants, studying risk reductions vs. the lowest tomato consumers. An inverse association between tomato consumption and diastolic blood pressure was observed between the intermediate group β = -0.65 mmHg [95% confidence interval (CI): -1.20, -0.10] and the lowest consumption group. A significant inverse association was observed for blood pressure in grade 1 hypertension participants in the intermediate tomato consumption group. The risk of hypertension decreased with consumption of >110 g/day tomato (highest vs. lowest consumption; hazard ratio, 0.64 [95% CI, 0.51-0.89]).

CONCLUSION

Tomato consumption, including tomato-based products, is beneficial in preventing and managing hypertension. Higher tomato intake reduces hypertension risk by 36%, and moderate consumption lowers blood pressure, especially in grade 1 hypertension.

Balancing Redox Homeostasis to Improve l-Cysteine Production in Corynebacterium glutamicum

l-Cysteine is a valuable sulfur-containing amino acid with applications across a wide range of fields. Recently, microbial fermentation has emerged as a method to produce l-cysteine. However, cellular redox stress from high levels of l-cysteine is a bottleneck for achieving efficient production. In this study, we aimed to facilitate l-cysteine biosynthesis by modulating cellular redox homeostasis through the introduction of the natural antioxidant astaxanthin in Corynebacterium glutamicum. To achieve this, we first introduced an exogenous astaxanthin synthesis module in C. glutamicum. Then, an l-cysteine-dependent autonomous bifunctional genetic switch was developed to dynamically regulate the l-cysteine and astaxanthin biosynthesis pathway to maintain cellular redox homeostasis. This regulation system achieved high biosynthesis of astaxanthin, which significantly facilitated l-cysteine production. Finally, engineered strain Cg-10 produced 8.45 g/L l-cysteine and 95 mg/L astaxanthin in a 5 L bioreactor, both of which are the highest reported levels in C. glutamicum.

Protective Effect of Natural Antioxidants on Reducing Cisplatin-Induced Nephrotoxicity

The clinical application of cisplatin is limited by its adverse events, of which nephrotoxicity is the most commonly observed. In a cisplatin-induced pathological response, oxidative stress is one of the upstream reactions which inflicts different degrees of damages to the intracellular material components. Reactive oxygen species (ROS) are also one of the early signaling molecules that subsequently undergo a series of pathological reactions, such as apoptosis and necrosis. This review summarizes the mechanism of intracellular ROS generation induced by cisplatin, mainly from the consumption of endogenous antioxidants, destruction of antioxidant enzymes, induction of mitochondrial crosstalk between the endoplasmic reticulum by ROS and Ca²⁺, and destruction of the cytochrome P450 (CYP) system in the endoplasmic reticulum, all of which result in excessive accumulation of intracellular ROS and oxidative stress. In addition, studies demonstrated that natural antioxidants can protect against the cisplatin-induced nephrotoxicity, by reducing or even eliminating excess free radicals and also affecting other nonredox pathways. Therefore, this review on the one hand provides theoretical support for the research and clinical application of natural antioxidants and on the other hand provides a new entry point for the detailed mechanism of cisplatin nephrotoxicity, which may lay a solid foundation for the future clinical use of cisplatin.

Halophilic Carotenoids and Breast Cancer: From Salt Marshes to Biomedicine

Breast cancer is the leading cause of death among women worldwide. Over the years, oxidative stress has been linked to the onset and progression of cancer. In addition to the classical histological classification, breast carcinomas are classified into phenotypes according to hormone receptors (estrogen receptor-RE-/progesterone receptor-PR) and growth factor receptor (human epidermal growth factor receptor-HER2) expression. Luminal tumors (ER/PR-positive/HER2-negative) are present in older patients with a better outcome. However, patients with HER2-positive or triple-negative breast cancer (TNBC) (ER/PR/HER2-negative) subtypes still represent highly aggressive behavior, metastasis, poor prognosis, and drug resistance. Therefore, new alternative therapies have become an urgent clinical need. In recent years, anticancer agents based on natural products have been receiving huge interest. In particular, carotenoids are natural compounds present in fruits and vegetables, but algae, bacteria, and archaea also produce them. The antioxidant properties of carotenoids have been studied during the last years due to their potential in preventing and treating multiple diseases, including cancer. Although the effect of carotenoids on breast cancer during in vitro and in vivo studies is promising, clinical trials are still inconclusive. The haloarchaeal carotenoid bacterioruberin holds great promise to the future of biomedicine due to its particular structure, and antioxidant activity. However, much work remains to be performed to draw firm conclusions. This review summarizes the current knowledge on pre-clinical and clinical analysis on the use of carotenoids as chemopreventive and chemotherapeutic agents in breast cancer, highlighting the most recent results regarding the use of bacterioruberin from haloarchaea.

Modulation of inflammation by phytochemicals to enhance efficacy and reduce toxicity of cancer chemotherapy

Treatment of cancer with chemotherapeutic drugs is associated with numerous adverse effects as well as the eventual development of resistance to chemotherapy. There is a great need for complementary therapies such as botanicals and nutritional supplements with little or no side effects that prevent resistance to chemotherapy and reduce its adverse effects. Inflammation plays a major role in the development of chemoresistance and the adverse effects of chemotherapy. Phytochemicals have well-established anti-inflammatory effects; thus, they could be used as complementary therapies along with chemotherapy to increase its efficacy and reduce its toxicity. Botanical compounds inhibit the NF-κB signaling pathway, which plays an important role in the generation of inflammation, chemotherapy resistance, and modulation of cell survival and apoptosis. Botanicals have previously been studied extensively for their cancer chemopreventive activities and are generally considered safe for human consumption. The present review focuses on the modulation of inflammation by phytochemicals and their role in increasing the efficacy and reducing the toxicity of cancer chemotherapy.

Phyto-Phospholipid Complexation as a Novel Drug Delivery System for Management of Cancer with Better Bioavailability: Current Perspectives and Future Prospects

Cancer is the foremost cause of death, and it supports the need for the identification of novel anticancer drugs to improve the efficacy of current-therapy. While the synthetic anticancer drug is associated with numerous side effects. Hence the plant active or phytoconstituents are in high demand for the treatment of cancer due to minimum side effects. But the polar nature of phytoconstituents hindered the absorption of the drug and lowered the therapeutic efficacy. The plant activity incorporated into Phyto-phospholipid Complexation can enhance bioavailability and improved therapeutic efficacy. In this review article, advantages, limitation and application of Phyto-phospholipid complexes have been illustrated. The article highlights the application of Phyto-phospholipid complexes as a promising drug carrier system to treat cancer.

Integrative Management of Pancreatic Cancer (PDAC): Emerging Complementary Agents and Modalities

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease. The standard first-line treatment for PDAC is gemcitabine chemotherapy which, unfortunately, offers only limited chance of a lasting cure. This review further evaluates the hypothesis that the effectiveness of gemcitabine can be improved by combining it with evidence-based complementary measures. Previously, supported by clinical trial data, we suggested that a number of dietary factors and nutraceuticals can be integrated with gemcitabine therapy. Here, we evaluate a further 10 agents for which no clinical trials have (yet) been carried out but there are promising data from in vivo and/or in vitro studies including experiments involving combined treatments with gemcitabine. Two groups of complementary agents are considered: Dietary factors (resveratrol, epigallocatechin gallate, vitamin B9, capsaicin, quercetin and sulforaphane) and nutraceutical agents (artemisinin, garcinol, thymoquinone and emodin). In addition, we identified seven promising agents for which there is currently only basic (mostly in vitro) data. Finally, as a special case of combination therapy, we highlighted synergistic drug combinations involving gemcitabine with "repurposed" aspirin or metformin. We conclude overall that integrated management of PDAC currently is likely to produce the best outcome for patients and for this a wide range of complementary measures is available.

Oxidative stress as an underlying mechanism of anticancer drugs cytotoxicity on human red blood cells' membrane

The aim of this study is to investigate the direct in vitro effects of anticancer drugs on red blood cells (RBCs) and to explore the underlying mechanism, mainly by measuring RBCs oxidative stress (OS) status. After RBCs direct contact with fourteen (14) anticancer drugs, several parameters were assessed including: cellular turbidity, methemoglobin (metHb) generation, released Hb and Hb stability. Moreover, intracellular Hb, considered as new molecular target of anticancer drugs, was quantified inside RBCs. MDA level, the main biomarker of OS, was simultaneously measured. The cellular turbidity reveled severe (docetaxel "TXT", 0.03 ± 0.002), moderate (methotrexate "MTX", 0.49 ± 0.009), or none (5-fluorouracil "5-FU", 0.76 ± 0.029) membrane cytotoxicity (MC). An inverse relationship between cell concentration, released Hb and metHb content was obtained. High metHb generation, revealing intense OS, was also mostly expressed in paclitaxel "TXL" and etoposide "VP16". Further, epirubicin "EPI" and "TXT" induced important oxidation of membrane lipids with 0.32 ± 0.014 and 0.26 ± 0.004, respectively. Also, MTX (0.17 ± 0.006) and doxorubicin "DOX" (0.32 ± 0.034) affected significantly Hb stability by a direct contact with molecule. These findings demonstrated that anticancer drugs have the ability to induce membrane damages by the exacerbation of OS through membrane lipid peroxidation and Hb oxidation even inside RBCs.

Sialic acid-conjugated PLGA nanoparticles enhance the protective effect of lycopene in chemotherapeutic drug-induced kidney injury

Lycopene (LYC) is known to protect cells from oxidative damage caused by free radicals in human tissues. In the present study, the authors designed a LYC-loaded sialic acid (SA)-conjugated poly(D,L-lactide-co-glycolide) (PLGA) nanoparticle (LYC-NP) to enhance the therapeutic efficacy of LYC in acute kidney injury. The characteristics of the LYC-NPs were defined according to particle size, morphology, and in vitro drug release. The LYC-NPs exhibited a controlled release of LYC over 48 h. Confocal laser scanning microscopy clearly highlighted the targeting potential of SA. Enhanced green fluorescence was observed for the LYC-NPs in H₂O₂-treated human umbilical vein endothelial cells, indicating enhanced internalisation of NPs. The LYC-NPs showed significantly greater cell viability than H₂O₂-treated cells. In addition, the LYC-NPs remarkably reduced proinflammatory cytokine levels, attributable mainly to the increased cellular internalisation of the SA-based carrier delivery system. Furthermore, protein levels of caspase-3 and -9 were significantly down-regulated after treatment with the LYC-NPs. Overall, they have demonstrated that SA-conjugated PLGA-NPs containing LYC could be used to treat kidney injury.

Molecular mechanism of olaquindox-induced hepatotoxicity and the hepatic protective role of curcumin

Olaquindox (OLA) is a chemosynthetic growth promoter, which could promote the treatment of bacterial infections and improve feed energy efficiency. Hepatotoxicity is still a poor feature associated with the adverse effects of OLA. The present study aimed to investigate the molecular mechanism of OLA-induced hepatotoxicity and the protective role of curcumin in mice and HepG2 cells. The result showed that representative biomarkers involved in mitochondrial pathway, p53 pathway, mitogen-activated protein kinase (MAPK) pathway, autophagy and antioxidant pathway were activated. Furthermore, curcumin attenuated OLA-induced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and liver damage in mice. In addition, cell viability of HepG2 was enhanced by curcumin pretreatment at 5, 10 and 20 μM. Meanwhile, curcumin markedly ameliorated OLA-induced oxidative stress, apoptosis and mitochondrial dysfunction. Moreover, curcumin pretreatment significantly up-regulated the expressions of nuclear factor erythroid-2-related factor 2 (Nrf2) and heme oxygenase-1(HO-1) and down-regulated the expressions of nuclear factor-kappaB (NF-kB) and p53 through reduced the nuclear translocation of NF-kB induced by OLA. In summary, our findings indicated that OLA-induced hepatotoxicity involved in mitochondrial apoptosis, autophagy, p53 pathway, Nrf2/HO-1 pathways, and curcumin regulated OLA-induced liver damage, oxidative stress and apoptosis via activation of Nrf2/HO-1 pathway and suppression of p53 and NF-kB pathway.

Curcuma longa normalized cimetidine-induced pituitary-testicular dysfunction: Relevance in nutraceutical therapy

BACKGROUND

The increasing incidence of chemically induced infertility is both a social threat and a threat to the continuation of life itself. Treatment or management therapy is often expensive. This study investigated the effects of acetone extract of a local plant (Curcuma longa) in a Wistar rat model of cimetidine-induced pituitary-testicular dysfunction.

METHODS

Thirty-five male Wistar rats were divided into 7 groups of 5 rats. After a phytochemical screening of an acetone extract of C. Longa, cimetidine and the extract at three doses, 200, 400 and 600 mg/kg, were orally co-administered to the rats for 28 consecutive days. Comparisons were made (at P < 0.05) against a control (2 mL/kg distilled water), a standard treatment group (cimetidine + 50 mg/kg vitamin C), a toxic group (60 mg/kg cimetidine) and a group receiving extract alone.

RESULTS

Cimetidine administration was associated with deleterious alterations to sperm motility, sperm count and sperm viability, as well as derangements in the plasma levels of FSH, LH and testosterone (P < 0.05). Both brain and testicular GSH and TBARS levels were significantly altered following cimetidine administration, and distortions were seen in the pituitary and testicular histoarchitecture. These changes were significantly normalized by co-administration of graded doses of the extract, with an associated improvement of both pituitary and testicular histology.

CONCLUSION

Acetone extract of C. Longa normalized cimetidine-induced pituitary-testicular dysfunction in Wistar rats. This presents the extract as a potential nutraceutical choice against chemically induced reproductive toxicity.

Tomato Powder Modulates NF-κB, mTOR, and Nrf2 Pathways during Aging in Healthy Rats

Purpose

In the present study, we aimed to investigate the effects of tomato powder (TP) on glucose and lipid metabolism, as well as oxidative stress and the NF-κB, mTOR, and Nrf2 pathways during the aging process in healthy rats.

Methods and Results

Male Wistar rats were randomly assigned to four groups as follows: (i) Control group 1 (n=15, 3-week old): rats were fed standard diet for 7 weeks; (ii) TP group 1 (n=15, 3-week old): rats were fed standard diet supplemented with TP for 7 weeks; (iii) Control group 2 (n=15, 8-week old): rats were fed standard diet for 69 weeks; and (iv) TP group 2 (8-week old): rats were fed standard diet supplemented with TP for 69 weeks. TP supplementation significantly reduced the hyperglycemia, hypertriglyceridemia, and hypercholesterolemia and improved liver function and kidney function in 77-week old rats compared with the control animals (P < 0.05). In addition, TP significantly decreased the serum and liver MDA levels (P < 0.003 and P < 0.001, respectively) while increasing the activities of liver SOD (P < 0.001), CAT (P < 0.008), and GPx (P < 0.01) compared with the control groups in both 10-week-old and 77-week-old rats (P < 0.05). Age-related increases in phosphorylation of NF-κBp65, mTOR, 4E-BP1, and P70S6K were observed in livers of 77-week-old rats compared to those of 10-week-old rats (P < 0.001). TP supplementation decreased the expression of NF-κBp65 and activation of mTOR, 4E-BP1, and P70S6K in livers of 77-week-old rats compared to the control animals. Moreover, TP supplementation significantly elevated Nrf2 expression in livers of both 10-week-old and 77-week-old rats (P < 0.05).

Conclusion

TP ameliorates age-associated inflammation and oxidative stress through the inhibition of NF-κBp65, mTOR pathways, and Nrf2 activation may explain the observed improvement in glucose and lipid metabolism as well as the improved liver and kidney functions.

Non-Provitamin A and Provitamin A Carotenoids as Immunomodulators: Recommended Dietary Allowance, Therapeutic Index, or Personalized Nutrition?

Vegetables and fruits contain non-provitamin A (lycopene, lutein, and zeaxanthin) and provitamin A (β-carotene, β-cryptoxanthin, and α-carotene) carotenoids. Within these compounds, β-carotene has been extensively studied for its health benefits, but its supplementation at doses higher than recommended intakes induces adverse effects. β-Carotene is converted to retinoic acid (RA), a well-known immunomodulatory molecule. Human interventions suggest that β-carotene and lycopene at pharmacological doses affect immune functions after a depletion period of low carotenoid diet. However, these effects appear unrelated to carotenoids and retinol levels in plasma. Local production of RA in the gut-associated lymphoid tissue, as well as the dependency of RA-induced effects on local inflammation, suggests that personalized nutrition/supplementation should be considered in the future. On the other hand, the differential effect of RA and lycopene on transforming growth factor-beta suggests that lycopene supplementation could improve immune functions without increasing risk for cancers. However, such preclinical evidence must be confirmed in human interventions before any recommendations can be made.

Phosphorylation of eIF2α suppresses cisplatin-induced p53 activation and apoptosis by attenuating oxidative stress via ATF4-mediated HO-1 expression in human renal proximal tubular cells

Cisplatin is one of the most widely used chemotherapeutic agents for the treatment of human cancers. However, the nephrotoxicity of cisplatin limits its use as a therapeutic agent. It has been suggested that oxidative stress and p53 activation play important roles in cisplatin-induced nephrotoxicity. It has been demonstrated that the eukaryotic translation initiation factor 2α (eIF2α) may protect HK-2 human renal proximal tubular cells against cisplatin-induced apoptosis through inhibition of reactive oxygen species (ROS)‑mediated p53 activation. The aim of the present study was to investigate the effects of siRNA‑mediated knockdown of the PKR-like endoplasmic reticulum kinase (PERK) gene, which induces the phosphorylation of eIF2α, or Sal003, a selective inhibitor of eIF2α dephosphorylation, on cisplatin‑induced apoptosis in HK-2 cells. Cisplatin induced eIF2α phosphorylation as well as p53 activation. In particular, inhibition of p53 by pifithrin‑α, and upregulation of eIF2α phosphorylation by Sal003, reduced cisplatin-induced apoptosis. Of note, Sal003‑mediated upregulation of eIF2α phosphorylation suppressed cisplatin‑induced p53 activation. Furthermore, reduction of eIF2α phosphorylation by PERK knockdown enhanced cisplatin-induced p53 activation and apoptosis. In addition, the ROS scavenger N-acetyl-L-cysteine inhibited eIF2α phosphorylation as well as p53 activation in HK-2 cells treated with cisplatin, suggesting that oxidative stress induced by cisplatin may lead to apoptosis through p53 activation; furthermore, this stress may confer resistance to apoptosis via eIF2α phosphorylation, which was further supported by the finding that cisplatin‑induced ROS generation was attenuated by Sal003, whereas it was enhanced by PERK knockdown. Furthermore, cisplatin induced the expression of activating transcription factor 4 (ATF4) and heme oxygenase-1 (HO-1) that were enhanced by Sal003 and reduced by PERK knockdown. Taken together, these results suggest that phosphorylation of eIF2α suppresses cisplatin‑induced p53 activation and apoptosis by attenuating oxidative stress via ATF4-mediated HO-1 expression in HK-2 cells, as ATF4 expression is usually dependent on the phosphorylation of eIF2α and may also transcriptionally induce the expression of HO-1 in response to oxidative stress. Therefore, regulation of eIF2α phosphorylation may play an important role in alleviating cisplatin-induced nephrotoxicity.

Plant-Derived Agents for Counteracting Cisplatin-Induced Nephrotoxicity

Cisplatin (CSP) is a chemotherapeutic agent commonly used to treat a variety of malignancies. The major setback with CSP treatment is that its clinical efficacy is compromised by its induction of organ toxicity, particular to the kidneys and ears. Despite the significant strides that have been made in understanding the mechanisms underlying CSP-induced renal toxicity, advances in developing renoprotective strategies are still lacking. In addition, the renoprotective approaches described in the literature reveal partial amelioration of CSP-induced renal toxicity, stressing the need to develop potent combinatorial/synergistic agents for the mitigation of renal toxicity. However, the ideal renoprotective adjuvant should not interfere with the anticancer efficacy of CSP. In this review, we have discussed the progress made in utilizing plant-derived agents (phytochemicals) to combat CSP-induced nephrotoxicity in preclinical studies. Furthermore, we have also presented strategies to utilize phytochemicals as prototypes for the development of novel renoprotective agents for counteracting chemotherapy-induced renal damage.

Neuro-endocrine effects of aqueous extract of Amaranthus viridis (Linn.) leaf in male Wistar rat model of cyclophosphamide-induced reproductive toxicity

Cyclophosphamide (CP) is a widely used cytotoxic alkylating agent with antitumor and immunosuppressant properties that is associated with various forms of reproductive toxicity. The significance of natural antioxidants of plant origin should be explored, especially in a world with increasing incidence of patients in need of chemotherapy. The neuro-endocrine effects of aqueous extract of Amaranthus viridis (Linn.) leaf (AEAVL) in Wistar rats with CP-induced reproductive toxicity was determined. Forty rats were used for this study such that graded doses of the extract were administered following CP-induced reproductive toxicity and comparisons were made against control, toxic and standard (vitamin E) groups at p < 0.05. The synthetic drugs (CP, 65 mg/kg i.p. for 5 days; Vitamin E, 100 mg/kg p.o. for 30 days) as well as the extract (100, 200 and 400 mg/kg p.o. for 30 days) were administered to the rats at 0.2 mL/100 g. CP induced reproductive toxicity as evidenced by significantly lowered levels of FSH, LH and testosterone, perturbation of sperm characterization, deleterious disruptions of the antioxidant system as evidenced by decreased levels of GSH as well as elevation of TBARS activity. Histopathological examination showed hemorrhagic lesions with scanty and hypertrophied parenchymal cells in the pituitary while the testis showed ballooned seminiferous tubules with loosed connective tissues and vacuolation of testicular interstitium. These conditions were significantly reversed (p < 0.05) following administration of the graded doses of the extract. It was, therefore, concluded that AEAVL could potentially be a therapeutic choice in patients with CP-induced neuro-endocrine dysfunction and reproductive toxicity.

Cardioprotective Potentials of Plant-Derived Small Molecules against Doxorubicin Associated Cardiotoxicity

Doxorubicin (DOX) is a potent and widely used anthracycline antibiotic for the treatment of several malignancies. Unfortunately, the clinical utility of DOX is often restricted due to the elicitation of organ toxicity. Particularly, the increased risk for the development of dilated cardiomyopathy by DOX among the cancer survivors warrants major attention from the physicians as well as researchers to develop adjuvant agents to neutralize the noxious effects of DOX on the healthy myocardium. Despite these pitfalls, the use of traditional cytotoxic drugs continues to be the mainstay treatment for several types of cancer. Recently, phytochemicals have gained attention for their anticancer, chemopreventive, and cardioprotective activities. The ideal cardioprotective agents should not compromise the clinical efficacy of DOX and should be devoid of cumulative or irreversible toxicity on the naïve tissues. Furthermore, adjuvants possessing synergistic anticancer activity and quelling of chemoresistance would significantly enhance the clinical utility in combating DOX-induced cardiotoxicity. The present review renders an overview of cardioprotective effects of plant-derived small molecules and their purported mechanisms against DOX-induced cardiotoxicity. Phytochemicals serve as the reservoirs of pharmacophore which can be utilized as templates for developing safe and potential novel cardioprotective agents in combating DOX-induced cardiotoxicity.

Lycopene attenuates colistin-induced nephrotoxicity in mice via activation of the Nrf2/HO-1 pathway

Nephrotoxicity is the major dose-limiting factor for the clinical use of colistin against multidrug-resistant (MDR) Gram-negative bacteria. This study aimed to investigate the protective effect of lycopene on colistin-induced nephrotoxicity in a mouse model. Fifty mice were randomly divided into 5 groups: the control group (saline solution), the lycopene group (20 mg/kg of body weight/day administered orally), the colistin group (15 mg/kg/day administered intravenously), the colistin (15 mg/kg/day) plus lycopene (5 mg/kg/day) group, and the colistin (15 mg/kg/day) plus lycopene (20 mg/kg/day) group; all mice were treated for 7 days. At 12 h after the last dose, blood was collected for measurements of blood urea nitrogen (BUN) and serum creatinine levels. The kidney tissue samples were obtained for examination of biomarkers of oxidative stress and apoptosis, histopathological assessment, and quantitative reverse transcription-PCR (qRT-PCR) analysis. Colistin treatment significantly increased concentrations of BUN and serum creatinine, tubular apoptosis/necrosis, lipid peroxidation, and heme oxygenase 1 (HO-1) activity, while the treatment decreased the levels of endogenous antioxidant biomarkers glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). Notably, the changes in the levels of all biomarkers were attenuated in the kidneys of mice treated with colistin by lycopene (5 or 20 mg/kg). Lycopene treatment, especially in the colistin plus lycopene (20 mg/kg) group, significantly downregulated the expression of NF-κB mRNA (P < 0.01) but upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and HO-1 mRNA (both P < 0.01) in the kidney compared with the results seen with the colistin group. Our data demonstrated that coadministration of 20 mg/kg/day lycopene can protect against colistin-induced nephrotoxicity in mice. This effect may be attributed to the antioxidative property of lycopene and its ability to activate the Nrf2/HO-1 pathway.

Carotenoids, inflammation, and oxidative stress--implications of cellular signaling pathways and relation to chronic disease prevention

Several epidemiologic studies have shown that diets rich in fruits and vegetables reduce the risk of developing several chronic diseases, such as type 2 diabetes, atherosclerosis, and cancer. These diseases are linked with systemic, low-grade chronic inflammation. Although controversy persists on the bioactive ingredients, several secondary plant metabolites have been associated with these beneficial health effects. Carotenoids represent the most abundant lipid-soluble phytochemicals, and in vitro and in vivo studies have suggested that they have antioxidant, antiapoptotic, and anti-inflammatory properties. Recently, many of these properties have been linked to the effect of carotenoids on intracellular signaling cascades, thereby influencing gene expression and protein translation. By blocking the translocation of nuclear factor κB to the nucleus, carotenoids are able to interact with the nuclear factor κB pathway and thus inhibit the downstream production of inflammatory cytokines, such as interleukin-8 or prostaglandin E2. Carotenoids can also block oxidative stress by interacting with the nuclear factor erythroid 2-related factor 2 pathway, enhancing its translocation into the nucleus, and activating phase II enzymes and antioxidants, such as glutathione-S-transferases. In this review, which is organized into in vitro, animal, and human investigations, we summarized current knowledge on carotenoids and metabolites with respect to their ability to modulate inflammatory and oxidative stress pathways and discuss potential dose-health relations. Although many pathways involved in the bioactivity of carotenoids have been revealed, future research should be directed toward dose-response relations of carotenoids, their metabolites, and their effect on transcription factors and metabolism.

Effect of lycopene against cisplatin-induced acute renal injury in rats: organic anion and cation transporters evaluation

In the present study, we investigated the effects of lycopene on the expression of organic anion transporters (OATs), organic cation transporters (OCTs), and multidrug resistance-associated proteins (MRPs) of cisplatin-induced nephrotoxicity in rats. Twenty-eight 8-week-old Wistar rats were divided into four groups: control, lycopene-treated (6 mg/kg BW by oral gavage), cisplatin-treated (7 mg/kg BW, IP), and lycopene in combination with cisplatin-treated groups. In the presence of cisplatin, serum urea nitrogen (urea-N) (48.5 vs. 124.3 mg/dl) and creatinine (0.29 vs. 1.37 mg/dl) levels and the kidney efflux transporters MRP2 and MRP4 levels were significantly increased, whereas OAT1, OAT3, OCT1, and OCT2 levels in kidney were decreased in the treated rats compared with normal control rats. However, administration of lycopene in combination with cisplatin resulted in a reduction in the serum urea-N (124.3 vs. 62.4) and creatinine (1.37 vs. 0.40) levels and the kidney efflux transporters MRP2 and MRP4 proteins in the kidneys. Administration of lycopene to acute renal injury-induced rats largely upregulated the organic anion transporters (OAT1 and 3) and organic cation transporters (OCT1 and 2) to decrease the side effects of cisplatin. The present study suggests that lycopene synergizes with its nephroprotective effect against cisplatin-induced acute kidney injury in rats.

Protective effect of diallyl disulfide on cyclophosphamide-induced testicular toxicity in rats

This study investigated the protective effects of diallyl disulfide (DADS) against cyclophosphamide (CP)-induced testicular toxicity in male rats. DADS was gavaged to rats once daily for 3 days at 100 mg/kg/day. One hour after the final DADS treatment, the rats were given a single intraperitoneal dose of 150 mg/kg CP. All rats were killed and necropsied on day 56 after CP treatment. Parameters of testicular toxicity included reproductive organ weight, testicular sperm head count, epididymal sperm motility and morphology, epididymal index, and histopathologic examinations. The CP treatment caused a decrease in body weight, testicular sperm head count, epididymal sperm motility, and epididymal index. The histopathological examination revealed various morphological alterations, characterized by degeneration of spermatogonia/spermatocytes, vacuolization, and decreased number of spermatids/spermatocytes in the testis, and cell debris and mild oligospermia in the ductus epididymis. In contrast, DADS pretreatment effectively attenuated the testicular toxicity caused by CP, including decreased sperm head count, epididymal sperm motility, and epididymal index and increased histopathological alterations in the testis and epididymis. These results indicate that DADS attenuates testicular toxicity induced by CP in rats.

Oxidative stress in apoptosis and cancer: an update

The oxygen paradox tells us that oxygen is both necessary for aerobic life and toxic to all life forms. Reactive oxygen species (ROS) touch every biological and medical discipline, especially those involving proliferative status, supporting the idea that active oxygen may be increased in tumor cells. In fact, metabolism of oxygen and the resulting toxic byproducts can cause cancer and death. Efforts to counteract the damage caused by ROS are gaining acceptance as a basis for novel therapeutic approaches, and the field of prevention of cancer is experiencing an upsurge of interest in medically useful antioxidants. Apoptosis is an important means of regulating cell numbers in the developing cell system, but it is so important that it must be controlled. Normal cell death in homeostasis of multicellular organisms is mediated through tightly regulated apoptotic pathways that involve oxidative stress regulation. Defective signaling through these pathways can contribute to both unbalance in apoptosis and development of cancer. Finally, in this review, we discuss new knowledge about recent tools that provide powerful antioxidant strategies, and designing methods to deliver to target cells, in the prevention and treatment of cancer.

Dietary emu oil supplementation suppresses 5-fluorouracil chemotherapy-induced inflammation, osteoclast formation, and bone loss

Cancer chemotherapy can cause osteopenia or osteoporosis, and yet the underlying mechanisms remain unclear, and currently, no preventative treatments are available. This study investigated damaging effects of 5-fluorouracil (5-FU) on histological, cellular, and molecular changes in the tibial metaphysis and potential protective benefits of emu oil (EO), which is known to possess a potent anti-inflammatory property. Female dark agouti rats were gavaged orally with EO or water (1 ml·day(-1)·rat(-1)) for 1 wk before a single ip injection of 5-FU (150 mg/kg) or saline (Sal) was given. The treatment groups were H(2)O + Sal, H(2)O + 5-FU, EO + 5-FU, and EO + Sal. Oral gavage was given throughout the whole period up to 1 day before euthanasia (days 3, 4, and 5 post-5-FU). Histological analysis showed that H(2)O + 5-FU significantly reduced heights of primary spongiosa on days 3 and 5 and trabecular bone volume of secondary spongiosa on days 3 and 4. It reduced density of osteoblasts slightly and caused an increase in the density of osteoclasts on trabecular bone surface on day 4. EO supplementation prevented reduction of osteoblasts and induction of osteoclasts and bone loss caused by 5-FU. Gene expression studies confirmed an inhibitory effect of EO on osteoclasts since it suppressed 5-FU-induced expression of proinflammatory and osteoclastogenic cytokine TNFα, osteoclast marker receptor activator of nuclear factor-κB, and osteoclast-associated receptor. Therefore, this study demonstrated that EO can counter 5-FU chemotherapy-induced inflammation in bone, preserve osteoblasts, suppress osteoclast formation, and potentially be useful in preventing 5-FU chemotherapy-induced bone loss.

Protective effects of lycopene on cerulein-induced experimental acute pancreatitis in rats

BACKGROUND

The purpose of our study was to evaluate the protective effect of the strong antioxidant and anti-inflammatory agent, lycopene, on oxidative stress in a rat model of cerulein-induced acute edematous pancreatitis.

METHODS

Sprague-Dawley rats were pretreated with lycopene (50 mg/kg, i.p.) or saline 15 min before cerulein was given 20 μg/kg (i.p.) at 1-h intervals within 4 h. Twelve hours after cerulein or saline injections, the animals were killed by decapitation. Blood samples were collected to analyze amylase, lipase, and proinflammatory cytokines (TNF-α and IL-1ß). Pancreatic tissues were taken for the determination of tissue glutathione (GSH) and malondialdehyde (MDA) levels, Na(+)/K(+)-ATPase, and myeloperoxidase (MPO) activities. Tissue samples were also examined histologically.

RESULTS

Acute pancreatitis caused significant decrease in tissue GSH levels and Na(+)/K(+)-ATPase activity, while pancreatic MDA levels and MPO activity were increased. Furthermore, TNF-α, IL-1ß, and amylase lipase levels were also significantly increased. On the other hand, lycopene pretreatment reserved all these biochemical indices as well as histopathologic alterations that were induced by cerulein.

CONCLUSIONS

According to the results, lycopene protects the pancreatic tissues from oxidative damage induced by cerulein, and this effect possibly involves the inhibition of neutrophil infiltration and lipid peroxidation. These results suggest that high dietary intake of tomatoes may have protective effects against acute pancreatitis.

Developing a highly stable PLGA-mPEG nanoparticle loaded with cisplatin for chemotherapy of ovarian cancer

Background

Cisplatin is a potent anticancer drug, but its clinical application has been limited due to its undesirable physicochemical characteristics and severe side effects. Better drug formulations for cisplatin are highly desired.

Methodology/Principal Findings

Herein, we have developed a nanoparticle formulation for cisplatin with high encapsulation efficiency and reduced toxicity by using cisplatin-crosslinked carboxymethyl cellulose (CMC) core nanoparticles made from poly(lactide-co-glycolide)-monomethoxy-poly(polyethylene glycol) copolymers (PLGA-mPEG). The nanoparticles have an average diameter of approximately 80 nm measured by transmission electron microscope (TEM). The encapsulation efficiency of cisplatin in the nanoparticles is up to 72%. Meanwhile, we have also observed a controlled release of cisplatin in a sustained manner and dose-dependent treatment efficacy of cisplatin-loaded nanoparticles against IGROV1-CP cells. Moreover, the median lethal dose (LD₅₀) of the cisplatin-loaded nanoparticles was more than 100 mg/kg by intravenous administration, which was much higher than that of free cisplatin.

Conclusion

This developed cisplatin-loaded nanoparticle is a promising formulation for the delivery of cisplatin, which will be an effective therapeutic regimen of ovarian cancer without severe side effects and cumulative toxicity.