Protective Effect of D-Methionine on Body Weight Loss, Anorexia, and Nephrotoxicity in Cisplatin-Induced Chronic Toxicity in Rats

The Nephroprotective Activity of Boesenbergia Rotunda Rhizome by Reducing Creatinine, Urea Nitrogen, Glutamic Pyruvic Transaminase, and Malondialdehyde Levels in the Blood and Attenuating the Expression of Havcr1 (KIM-1), Lcn2 (NGAL), Casp3, and Casp7 Genes in the Kidney Cortex of Cisplatin-Induced Sprague-Dawley Rats

Background

Cisplatin chemotherapy induces nephrotoxicity by producing reactive oxygen species, hence, discovering add-on nephroprotective drugs for patients with cancer is challenging. Boesenbergia rotunda has been reported for its antioxidant properties.

Purpose

This study aims to explore the nephroprotective mechanism of the ethanol extract of Boesenbergia rotunda rhizome (EEBR) in cisplatin-induced rats.

Methods

The rats were randomly assigned into 6 groups: the normal control (treated with saline); the negative control (cisplatin-induced without any treatment); the positive control (treated with quercetin 50 mg/kg BW); and 3 treatment EEBR (125 mg/kg BW; 250 mg/kg BW; 500 mg/kg BW) groups for 10 days. The % relative organ weight, kidney histopathology, and nephrotoxicity biomarkers expression were evaluated.

Results

EEBR decreased creatinine, urea nitrogen, glutamic pyruvate transaminase, and malondialdehyde levels in the blood of cisplatin-induced rats. An insignificant increase in GOT was observed in rats treated with the highest dose of EEBR. EEBR did not significantly alter the BW and the % kidney relative weight. An abnormal shape of the Bowman capsule is observed in the negative control group. EEBR reduced the expression of Havcr1 (KIM-1), Lcn2 (NGAL), Casp3, and Casp7 genes in rats' kidneys.

Conclusion

Boesenbergia rotunda could be considered a potential candidate for add-on therapy in cisplatin-treated patients, but further studies are needed to verify its efficacy and safety.

Exercise alleviates cisplatin-induced toxicity in the hippocampus of mice by inhibiting neuroinflammation and improving synaptic plasticity

Chemotherapy-induced cognitive impairment is recognized as the most typical symptom in patients with cancer that occurs during and following the chemotherapy treatment. Recently many studies focused on pharmaceutical strategies to control the chemotherapy side effects, however it is far from satisfactory. There may be a need for more effective treatment options. The aim of this study was to investigate the protective effect of exercise on cisplatin-induced neurotoxicity. Eightweek- old C57BL6 mice were separated into three group: normal control (CON, n = 8); cisplatin injection control (Cis-CON, n = 8); cisplatin with aerobic exercise (Cis-EXE, n = 8). Cisplatin was administered intraperitoneally at a dose of 3.5 mg/kg/day. The Cis-EXE group exercise by treadmill running (14-16 m/min for 45 min daily, 3 times/ week) for 12 weeks. Compared to the CON group, the cisplatin injection groups showed significant decrease in body weight and food intake, indicating successful induction of cisplatin toxicity. The Cis-CON group showed significantly increased levels of pro-inflammatory cytokines including IL-6, IL-1β, and TNF-α in the hippocampus, while the Cis-EXE group was significantly decreased in the expression of IL- 6, IL-1β, and TNF-α. In addition, compared to the CON group, the levels of synapserelated proteins including synapsin-1 and -2 were significantly reduced in the Cis- CON group, and there was a significant difference between the Cis-CON and Cis-EXE groups. Antioxidant and apoptosis factors were significantly improved in the Cis-EXE group compared with the Cis-CON group. This study suggest that exercise could be meaningful approach to prevent or improve cisplatin-induced cognitive impairment.

L-methionine protects against nephrotoxicity induced by methotrexate through modulation of redox status and inflammation

Objective: Methotrexate (MTX) is a drug used in the treatment of cancer and autoimmune disorders; however, its clinical use is limited because of serious side effects including renal toxicity. This study aimed to investigate the protective effect of Lmethionine (L-Met) on MTX toxicity in the kidneys of rats.Methods: Thirty male rats were divided equally into five groups: control (saline), Met400 (400 mg/kg L-Met), MTX (20 mg/kg MTX), MTX-Met300 (300 mg/kg L-Met and 20 mg/kg MTX), and MTX-Met400 (400 mg/kg L-Met and 20 mg/kg MTX). Rats were euthanized one day after the last dose administration (day 16) and serum and renal tissue samples were collected. Renal function and injury indices, oxidative stress/antioxidant indices and proinflammatory cytokines were evaluated.Results: The results showed that L-Met could effectively counteract the nephrotoxic effects of MTX, in a dose-related manner, by improving most of the tested parameters. Furthermore, the higher dose of L-Met was able to restore several parameters to normal levels. In addition, investigation of MTX-induced hematological changes revealed a corrective potential of L-Met.Conclusion: L-Met can be an effective adjuvant therapy to modulate renal toxicity associated with MTX because of its antioxidant and antiinflammatory effects.

Investigating the Replacement of Carboxylates with Carboxamides to Modulate the Safety and Efficacy of Platinum(II) Thioether Cyanide Scavengers

Cyanide represents a persistent threat for accidental or malicious misuse due to easy conversion into a toxic gas and access to large quantities through several industries. The high safety index of hydroxocobalamin is a cornerstone quality as a cyanide scavenger. Unfortunately, intravenous infusion of hydroxocobalamin limits the utility in a mass casualty setting. We previously reported platinum(II) [Pt(II)] complexes with trans-directing sulfur ligands as an efficacious alternative to hydroxocobalamin when delivered by a bolus intramuscular injection in mice and rabbits. Thus, to enable Pt(II) as an alternative to hydroxocobalamin, a high safety factor is needed. The objective is to maintain efficacy and mitigate the risk for nephrotoxicity. Platinum amino acid complexes with the ability to form five- or six-membered rings and possessing either carboxylates or carboxamides are evaluated in vitro for cyanide scavenging. In vivo efficacy was evaulated in the zebrafish and mice cyanide exposure models. In addition, Pt(II) complex toxicity and pharmacokinetics were evaluated in a cyanide naive Sprague-Dawley model. Doses for toxicity are escalated to 5x from the efficacious dose in mice using a body surface area adjustment. The results show the carboxamide ligands display a time and pH dependence on cyanide scavenging in vitro and efficacy in vivo. Additionally, exchanging the carboxylate for carboxamide showed reduced indications of renal injury. A pharmacokinetic analysis of the larger bidentate complexes displayed rapid absorption by intramuscular administration and having similar plasma exposure. These findings point to the importance of pH and ligand structures for methionine carboxamide complexes with Pt(II).

Oxidative Damage as a Fundament of Systemic Toxicities Induced by Cisplatin-The Crucial Limitation or Potential Therapeutic Target?

Cisplatin, an inorganic complex of platinum, is a chemotherapeutic drug that has been used for 45 years. Despite the progress of pharmaceutical sciences and medicine and the successful application of other platinum complexes for the same purpose, cisplatin is still the therapy of choice in many cancers. Treatment for testicular, ovarian, head and neck, urothelial, cervical, esophageal, breast, and pulmonary malignancies is still unthinkable without the use of this drug. However, cisplatin is also known for many side effects, of which the most pronounced are nephrotoxicity leading to acute renal failure, neurotoxicity, and ototoxicity. Mechanistic studies have proven that one of the conditions that plays a major role in the development of cisplatin-induced toxicities is oxidative stress. Knowing the fact that numerous antioxidants can be used to reduce oxidative stress, thereby reducing tissue lesions, organ failure, and apoptosis at the cellular level, many studies have defined antioxidants as a priority for investigation as a cotreatment. To investigate the mechanism of antioxidant action in vivo, many animal models have been employed. In the last few years, studies have mostly used rodents and zebrafish models. In this article, some of the most recent investigations that used animal models are listed, and the advantages and disadvantages of such experimental studies are pointed out.

Ameliorative Effect of Olea europaea Leaf Extract on Cisplatin-Induced Nephrotoxicity in the Rat Model

Background

Olea europaea leaf extract (OELE) has potential health benefits and protects against cytotoxicity. This study investigated the possible ameliorative effect of OELE on cisplatin-induced nephrotoxicity in rats.

Methods

Rats were assigned into six groups; two groups received 150 mg/kg or 300 mg/kg of OELE, one group received a single dose of cisplatin (6 mg/kg) IP on the first day of the experiment, two groups received a single dose of cisplatin 150 mg/kg or 300 mg/kg of OELE on the first day then starting from the fifth day for 10 consecutive days, and one group acted as a control. Results and Conclusion. The findings showed that cisplatin-induced nephrotoxicity was evidenced by a significant increase in serum creatinine blood urea nitrogen (BUN) and a significant decrease in estimated creatinine clearance and potassium level, which corresponded with the alterations in the histopathology of the renal tissue. OELE significantly ameliorated the nephrotoxic effects of cisplatin as dose-dependent.

Cardioprotective and renoprotective effects of venlafaxine on cisplatin-induced cardiotoxicity and nephrotoxicity in rats

AIM

The current work aims to demonstrate the potential defensive function of venlafaxine (VLF) in cardiotoxicity and nephrotoxicity caused by cisplatin (CP), that could be by modulating extracellular signal-regulated kinase (ERK)1/2 and nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase NOX4 pathways.

MAIN METHODS

Five groups of rats were used, as follow: three control groups (control, carboxymethyl cellulose, and VLF), CP group got CP once (7 mg/kg, intraperitoneally, i.p.), and (CP+ VLF) group got CP once then after 1 h they got VLF {50 mg/kg daily, orally for 14 days}. At the end of the study; electrocardiogram (ECG) was recorded for anaesthized rats then blood samples and tissues were taken for biochemical and histopathological investigations. Caspase 3, a marker of cellular damage and apoptosis was detected by immunohistochemistry.

KEY FINDINGS

CP treatment significantly impaired cardiac functions as evidenced by changes in rats' ECG. Cardiac enzymes, renal markers and inflammatory markers were increased with decreased activities of the total antioxidant capacity, superoxide dismutase and glutathione peroxidase. Also, ERK1/2 and NOX4 were upregulated with histopathological and immunohistochemical alterations of heart and kidney. While, VLF markedly alleviated CP-induced functional cardiac abnormalities and improved ECG pattern. It reduced both cardiac and renal biomarkers, oxidative stress, proinflammatory cytokine with ERK1/2 and NOX4 downregulation, improved the histopathological and immunohistochemical changes induced by cisplatin in heart and kidney.

SIGNIFICANCE

VLF treatment impedes cardiotoxicity and nephrotoxicity caused by CP. This beneficial effect was mediated through reduction of oxidative stress, inflammation, and apoptosis by targeting the ERK1/2 and NOX4.

Nephroprotective Effect of Diosmin against Cisplatin-Induced Kidney Damage by Modulating IL-1β, IL-6, TNFα and Renal Oxidative Damage

Cisplatin (CP) is a platinum compound of the alkylating agent class that is used for the treatment of various types of cancer. However, CP treatments in cancer patients are accountable for nephrotoxicity, as it is a major adverse effect. Hence, this research study was proposed to investigate the nephroprotective effect of diosmin, a flavonoid glycoside of hesperidin derivatives against cisplatin-induced kidney damage. Wistar rats received a single intraperitoneal (i.p) injection of CP (7.5 mg/kg, i.p) to induce nephrotoxicity. The administration of CP significantly (p < 0.001) increased the markers of kidney function test (creatinine, blood urea nitrogen, and uric acid) and demonstrated histopathological changes in the kidney of the CP-treated nephrotoxic group. In addition, the CP-treated nephrotoxic group demonstrated a significant (p < 0.001) increase in lipid peroxidation (LPO) levels and depleted activities of reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD) and catalase (CAT).However, diosmin (100 and 200 mg/kg) treatments significantly reduced the elevated levels of kidney function test parameters and restored structural changes in the kidney (p < 0.001). The administration of diosmin (100 and 200 mg/kg) significantly (p < 0.001) reduced LPO levels, increased GSH content and showed improvements in the activities of GPx, GR, SOD and CAT. The markers of inflammatory cytokines such as IL-1β, IL-6 and TNFα significantly (p < 0.001) increased in the CP-treated nephrotoxic group, whereas diosmin (100 and 200 mg/kg) treatments significantly (p < 0.001) reduced the elevated levels of these cytokines. The findings of this research demonstrate the nephroprotective effect of diosmin against CP-induced kidney damage. Therefore, we conclude that diosmin may be used as a supplement in the management of nephrotoxicity associated with CP treatments in cancer patients.

Cisplatin-Induced Nausea and Vomiting: Effect of Herbal Medicines

Cisplatin is a chemotherapeutic agent that is widely used to treat various types of cancers. However, its side effects, most commonly nausea and vomiting, limit its widespread use. Although various drugs, such as ondansetron and aprepitant, are used to alleviate these side effects, their efficacy is still debated. This review aims to summarize the results of 14 studies on the effects of seven single herbal extracts, one multiple herbal extract, and one ginger sub-component (i.e., [6]-gingerol) on cisplatin-induced nausea and vomiting. The results of the included studies were subdivided into four categories: kaolin consumption, retching and vomiting, food intake, and weight loss. Most studies used rodents, whereas four studies used minks or pigeons. The doses of cisplatin used in the studies varied from 3 mg/kg to 7.5 mg/kg, and only a single injection was used. Nine studies analyzed the mechanisms of action of herbal medicines and assessed the involvement of neurotransmitters, cytokines, enzymes, and various hematological parameters. Although further research is needed, this review suggests herbal medicine as a viable treatment option for cisplatin-induced neuropathic pain.

Effect and Mechanism of Herbal Medicines on Cisplatin-Induced Anorexia

Cisplatin is a well-known chemotherapeutic agent used to treat various types of cancers; however, it can also induce anorexia, which results in reduced food intake, loss of body weight, and lower quality of life. Although drugs such as megestrol acetate and cyproheptadine are used to decrease this severe feeding disorder, they can also induce side effects, such as diarrhea and somnolence, which limit their widespread use. Various types of herbal medicines have long been used to prevent and treat numerous gastrointestinal tract diseases; however, to date, no study has been conducted to analyze and summarize their effects on cisplatin-induced anorexia. In this paper, we analyze 12 animal studies that used either a single herbal medicine extract or mixtures thereof to decrease cisplatin-induced anorexia. Among the herbal medicines, Ginseng Radix was the most used, as it was included in seven studies, whereas both Glycyrrhizae Radix et Rhizoma and Angelicae Gigantis Radix were used in four studies. As for the mechanisms of action, the roles of serotonin and its receptors, cytokines, white blood cells, ghrelin, and leptin were investigated. Based on these results, we suggest that herbal medicines could be considered a useful treatment method for cisplatin-induced anorexia.

Evaluation of Renoprotective Effects of Our Locally Grown Green Coffee Beans against Cisplatin-Induced Nephrotoxicity in Swiss Albino Mice

INTRODUCTION

Nephrotoxicity is the most common and severe side effect of cisplatin. Cisplatin causes nephrotoxicity through free radical production and debilitating cellular antioxidant capacity. Coffee is a commonly consumed drink and its ingredients have antioxidant roles that could bring benefits to patients affected by nephrotoxicity. Thus, the present study aimed to investigate the renoprotective effects of our locally grown green coffee beans against cisplatin-induced nephrotoxicity in Swiss albino mice.

METHODS

The posttest only control group design was employed on a total of thirty male Swiss albino mice. The mice were divided into five groups: group I (normal control group) received distilled water; group II (negative control group) received distilled water; and groups III-V (treatment groups) received 100, 200, and 300 mg/kg BW/day of green coffee bean extract for 14 days, respectively. Nephrotoxicity was induced in groups II-V by a single intraperitoneal injection of cisplatin (7.5 mg/kg). All mice were sacrificed after 14 days and blood was drawn to evaluate kidney function tests (serum creatinine and serum blood urea nitrogen). Besides, body weight, relative kidney weight, and kidney histopathology were investigated.

RESULT

Our results showed that treatment of cisplatin alone (group II mice) significantly increased serum creatinine, serum blood urea nitrogen, relative kidney weight, and pathological damage to the kidney with a decrease in final body weight. However, low-dose green coffee beans (group III), medium-dose green coffee beans (group IV), and high-dose green coffee beans (group V) mice showed a significant dose-dependent decrease in serum creatinine, serum blood urea nitrogen, and relative kidney weight. Furthermore, the dose-dependent treatment with green coffee bean extract prevented the decrease in body weight gain and pathological damage to the kidney in mice.

CONCLUSION

Our locally grown green coffee beans brought a dose-dependent ameliorative effect and a promising preventive approach against cisplatin-induced kidney damage in mice.

Morphine Deteriorates Cisplatin-Induced Cardiotoxicity in Rats and Induces Dose-Dependent Cisplatin Chemoresistance in MCF-7 Human Breast Cancer Cells

Morphine (MOR) is a strong analgesic that is often used in treatment of severe pains during cancer treatment, and thus might be concomitantly used with anticancer drugs as cisplatin (CP). The aim of the current study was to investigate the mechanisms by which MOR can affect CP-induced cardiotoxicity and to explore effects of MOR on the cytotoxic efficacy of CP. MOR (10 mg/kg/day i.p.) was administered to rats for 10 days, with or without 7.5 mg/kg CP single i.p. dose at day 5 of the experiment. In addition, MOR and/or CP were administered to MCF-7 cells to test their cytotoxicity. Compared to control, CP caused cardiotoxic effects manifested by significant increase in serum enzymatic markers; creatine kinase-MB and lactate dehydrogenase, with histopathological cardiac damage. In addition, CP caused cardiac oxidative stress, manifested by significant increased tissue lipid peroxidation product; malondialdehyde and nitric oxide, with significant decrease in tissue antioxidants as reduced glutathione, superoxide dismutase and catalase compared to control. Furthermore, CP significantly increased tissue proinflammatory cytokines; TNF-α and IL-6, as well as upregulated the apoptotic marker; caspase 3 compared to control. MOR/CP combination significantly deteriorated all tested parameters compared to CP alone. In MCF-7 breast cancer cells, administration of MOR in concentrations of 0.1, 1, 10 or 30 μM concomitantly with 1 or 10 μM CP caused dose-dependent reduction in CP-induced cytotoxicity in vitro. In conclusion, MOR administration might deteriorate CP-induced cardiotoxicity during cancer chemotherapy through oxidant, pro-inflammatory and apoptotic mechanisms, and might reduce CP chemotherapeutic efficacy.

Effect of dietary inclusion of pumpkin (Cucurbita pepo L) seed on nephrotoxicity occasioned by cisplatin in experimental rats

The study evaluated the effect of dietary inclusion of pumpkin (Cucurbita pepo L) seed (raw and roasted) on nephrotoxicity caused by cisplatin in rats. Rats were divided into control group, cisplatin-induced nephrotoxic untreated group, nephrotoxic-treated groups with Methimazole, dietary regimen containing raw pumpkin seed (5% and 10%) and roasted pumpkin seed (5% and 10%) for 14 days. Results acquired uncovered that cisplatin intoxication significantly increased (p ≤ .05) the levels of renal biomarkers, arginase activity, 8-hydroxy-21 -deoxy guanosine (8-OHdG), malondialdehyde (MDA), and reactive oxygen species (ROS) levels as well as significant decrease in functional sulfhydryl groups, nitric oxide levels, and antioxidant enzyme activities in rats' kidney when compared to the control group. These adverse changes, due to cisplatin inebriation in rodents, were in any case, forestalled by pre-treatment with pumpkin seed inclusive diet. This holds promise for the use of pumpkin seed as a food supplement in the management of nephrotoxic-related disorders. PRACTICAL APPLICATIONS: These results suggest that roasted pumpkin seed appears to be more nephroprotective than the raw pumpkin seed through regulations of arginase activity, enhancement in the antioxidant system, suppression of renal markers and lipid peroxidation. This holds p-omise for the use of roasted pumpkin seed as a food supplement in the management nephrotoxic-related disorders.

D-methionine improves cisplatin-induced anorexia and dyspepsia syndrome by attenuating intestinal tryptophan hydroxylase 1 activity and increasing plasma leptin concentration

BACKGROUND

Cisplatin is a widely used antineoplastic drug. However, cisplatin-induced dyspepsia syndromes, including delayed gastric emptying, gastric distension, early satiety, nausea, and vomiting, often force patients to take doses lower than those prescribed or even refuse treatment. D-methionine has an appetite-enhancing effect and alleviates weight loss during cisplatin treatment.

METHODS

This work established a model of anorexia and dyspepsia symptoms with intraperitoneal injection of cisplatin (5 mg/kg) once a week for three cycles. Presupplementation with or without D-methionine (300 mg/kg) was performed. Orexigenic and anorexigenic hormones (ghrelin, leptin, and glucagon-like peptide-1), tryptophan hydroxylase 1 (TPH1), 5-hydroxytryptamine receptors (5-HT_2C and 5-HT₃ ), and hypothalamic feeding-related peptides were measured by immunohistochemistry staining, enzyme-linked immunosorbent assay, and real-time PCR assay.

KEY RESULTS

Cisplatin administration caused marked decrease in appetite and body weight, promoted adipose and fat tissue atrophy, and delayed gastric emptying and gastric distension, and D-methionine preadministration prior to cisplatin administration significantly ameliorated these side effects. Besides, cisplatin induced an evident increase in serum ghrelin level, TPH1 activity, and 5-HT₃ receptor expression in the intestine and decreased plasma leptin levels and gastric ghrelin mRNA gene expression levels. D-methionine supplementation recovered these changes. The expression of orexigenic neuropeptide Y/agouti-related peptide and anorexigenic cocaine- and amphetamine-regulated transcript proopiomelanocortin neurons were altered by D-methionine supplementation in cisplatin-induced anorexia rats.

CONCLUSIONS AND INFERENCES

D-methionine supplementation prevents cisplatin-induced anorexia and dyspepsia syndrome possibly by attenuating intestinal tryptophan hydroxylase 1 activity and increasing plasma leptin concentration. Therefore, D-methionine can be used as an adjuvant therapy for treating cisplatin-induced adverse effects.

Cisplatin-Induced Skeletal Muscle Dysfunction: Mechanisms and Counteracting Therapeutic Strategies

Among the severe side effects induced by cisplatin chemotherapy, muscle wasting is the most relevant one. This effect is a major cause for a clinical decline of cancer patients, since it is a negative predictor of treatment outcome and associated to increased mortality. However, despite its toxicity even at low doses, cisplatin remains the first-line therapy for several types of solid tumors. Thus, effective pharmacological treatments counteracting or minimizing cisplatin-induced muscle wasting are urgently needed. The dissection of the molecular pathways responsible for cisplatin-induced muscle dysfunction gives the possibility to identify novel promising therapeutic targets. In this context, the use of animal model of cisplatin-induced cachexia is very useful. Here, we report an update of the most relevant researches on the mechanisms underlying cisplatin-induced muscle wasting and on the most promising potential therapeutic options to preserve muscle mass and function.

D-Methionine Ameliorates Cisplatin-Induced Muscle Atrophy via Inhibition of Muscle Degradation Pathway

Cisplatin induces anorexia, weight loss, loss of adipose tissue, skeletal muscle atrophy, and serious adverse effects that can cause premature termination of chemotherapy. The aim of this study was to use an animal model to assess cisplatin therapy (3 cycles) with and without d-methionine to investigate its protective effects on cisplatin-induced anorexia and skeletal muscle wasting. Wistar rats were divided into 3 groups and treated as follows: saline as control (group 1), intraperitoneal cisplatin once a week for 3 weeks (group 2), and intraperitoneal cisplatin once a week for 3 weeks plus oral administration of d-methionine (group 3). Tissue somatic index (TSI), gastric emptying index (GEI), and feeding efficiency were measured. Both hepatic lipid metabolism and muscle atrophy-related gene expressions and C2C12 myotubes were determined by polymerase chain reaction. Micro-computed tomography (micro-CT) was used to conduct assessment of bone microarchitecture indices. Pathological changes of the gastric mucosa were assessed by hematoxylin and eosin staining after euthanizing the animals. d-Methionine increased food intake, weight gain, gastric emptying, and feeding efficiency, as well as decrease stomach contents, after cisplatin injections. Cisplatin caused shortening of myofibers. Cisplatin-induced muscle mass wasting was mediated by the elevation of mRNA expressions of MAFbx and MuRF-1 in ubiquitin ligases in muscle tissue homogenate. The mRNA expressions of MyoD and myogenin, markers of muscle differentiation, declined following cisplatin administration. The administration of d-methionine not only led to significant improvements in myofiber diameter and cross-sectional fiber areas but also reversed muscle atrophy-related gene expression. However, there were no significant changes in stomach histology or microarchitecture of trabecular bone among the study groups. The results indicate that d-methionine has an appetite-enhancing effect and ameliorates cisplatin-induced adipose and muscle tissue loss during cisplatin-based chemotherapy.

Cisplatin induces calcium ion accumulation and hearing loss by causing functional alterations in calcium channels and exocytosis

In recent years, molecular biology and biochemistry have been a focus of studies on the ototoxic side effects of cisplatin. In this paper, the application of cisplatin for 4 h and 72 h was studied from the perspective of electrophysiological function. Patch clamp experiments and immunofluorescence staining were performed on inner hair cells of the cochlea. The patch-clamp results showed that the calcium current amplitude decreased significantly at 4 h and 72 h after cisplatin treatment, the reversal potential was negatively polarized, and the activation time decreased. We suspected that intracellular calcium accumulation was responsible for this result and confirmed this hypothesis by using calpain to measure intracellular calcium concentrations. We tested membrane capacitive function, whose levels after cisplatin application were significantly lower than those in the control group, thus indicating dysfunctional cytoplasmic effervescent function. CtBP2 staining was used to verify this result and indicated a decrease in ribbon synapses. Simultaneously, we observed dysfunction of vesicle circulation after cisplatin application. We found that cisplatin induces the accumulation of calcium ions in inner hair cells by calpain staining and fluoresce intensity calculation, thus decreasing calcium current and synaptic vesicle release, and impairing vesicles cycling, all of which are important mechanisms of cisplatin-induced hearing loss.

Protective effect of avenanthramides against cisplatin induced nephrotoxicity in rats

Objective:

The aim of this study is to inspect the ameliorative effect of avenanthramides (AVA) on CP nephrotoxicity in Sprague-Dawley rats.

Materials and Methods:

Blood samples were collected for the determination of hematological parameters. Creatinine, blood urea nitrogen (BUN), and tumor necrosis factor-α (TNF-α) were measured in serum. Specimens from both kidneys were taken for histopathological examinations.

Results:

Administration of AVA resulted in significant decrease in the level of creatinine and TNF-α when compared with CP group. Histopathologically, CP-induced vacuolar degeneration and necrosis of the kidney tubules. Administration of AVA ameliorates the histopathological alterations induced by CP.

Conclusion:

AVA can be considered as a protective agent for kidneys during administration of CP. The protective effect of AVA may be related to the reduction of TNF-α which implicated in the pathogenesis of CP nephrotoxicity.

l-Methionine activates Nrf2-ARE pathway to induce endogenous antioxidant activity for depressing ROS-derived oxidative stress in growing rats

BACKGROUND

Methionine is an essential sulfur-containing amino acid. To elucidate the influence of l-methionine on activation of the nuclear factor erythroid 2-related factor 2-antioxidant responsive element (Nrf2-ARE) antioxidant pathway to stimulate the endogenous antioxidant activity for depressing reactive oxygen species (ROS)-derived oxidative stress, male Wistar rats were orally administered l-methionine daily for 14 days.

RESULTS

With the intake of l-methionine, Nrf2 was activated by l-methionine through depressing Keap1 and Cul3, resulting in upregulation of ARE-driven antioxidant expression (glutamate cysteine ligase catalytic subunit, glutamate cysteine ligase modulatory subunit, glutathione synthase (GS), catalase (CAT), superoxide dismutase (SOD), heme oxygenase 1, NAD(P)H:quinone oxidoreductase 1, glutathione reductase (GR), glutathione S-transferase (GST), glutathione peroxidase (GPx)) with increasing l-methionine availability. Upon activation of Nrf2, glutathione synthesis was increased through upregulated expression of methionine adenosyltransferase, S-adenosylhomocysteine hydrolase, cystathionine β-synthase, cystathionine γ-lyse, glutamate cysteine ligase (GCL) and GS, while hepatic expressions of methionine sulfoxide reductases (MsrA, MsrB2, MsrB3) and hepatic enzyme activities (CAT, SOD, GCL, GR, GST, GPx) were uniformly stimulated with increasing consumption of l-methionine. As a result, hepatic content of ROS and MDA were effectively reduced by l-methionine intake.

CONCLUSION

The present study demonstrates that methionine availability plays a critical role in activation of the Nrf2-ARE pathway to induce an endogenous antioxidant response for depressing ROS-derived oxidative stress, which is primarily attributed to the stimulation of methionine sulfoxide reductase expression and glutathione synthesis. © 2019 Society of Chemical Industry.

Protective Role of Epigallocatechin Gallate in a Rat Model of Cisplatin-Induced Cerebral Inflammation and Oxidative Damage: Impact of Modulating NF-κB and Nrf2

Cisplatin is a widely used chemotherapeutic agent in treating various types of cancers. However, it can induce neurotoxicity and nephrotoxicity, limiting its dose and clinical use. Although previous studies indicated the direct link between cisplatin-induced central neurotoxicity and oxidative stress, the exact mechanism is not completely understood. Therefore, herein we investigated the effects of prophylactic and concurrent treatment with (-)-epigallocatechin-3-gallate (EGCG), a natural polyphenolic neuroprotective antioxidant, on cisplatin-induced brain toxicity in rats to delineate its molecular mechanism of action. We found that cisplatin initiated a cascade of genetic, biological, and histopathological changes in the brain cortex, inducing inflammatory cytokines, appearance of scattered inflammatory cells, nitro-oxidative stress, and apoptotic proteins in the cerebral cortex. However, EGCG not only protected against cisplatin-induced inflammatory burden but also ameliorated the induction of nitro-oxidative stress and apoptotic proteins triggered by cisplatin in the cerebral cortex of pre- and co-treated rats with respect to their unprotected counterparts. EGCG anti-inflammatory effect here may be attributed to the downregulation of nuclear factor kappa B (NF-κB). Additionally, this natural polyphenol significantly ameliorated cisplatin-elicited reduction in cerebral cortex brain-derived neurotrophic factor and acetylcholine esterase. Upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream heme oxygenase-1 (HO-1) by EGCG prophylactic and concurrent administration here seems also to play a key role in the protective impact of EGCG against cisplatin toxicity through enhancing total antioxidant capacity. Thus, EGCG can be used as a promising prophylactic adjuvant for preventing the development of brain inflammation and oxidative damage associated with cisplatin chemotherapy.

Hyposalivation due to chemotherapy exacerbates oral ulcerative mucositis and delays its healing

OBJECTIVES

Cancer therapy including chemotherapy causes gland atrophy, resulting in low salivary secretion in cancer patients. Since saliva plays an important role in oral health, the dysfunction may exacerbate oral ulcerative mucositis (OUM), which is another side effect. Here, we investigated the effect of hyposalivation on OUM using sialoadenectomized rats and examined the effects of anticancer drugs on the salivary glands.

DESIGN

As models for hyposalivation, the bilateral submandibular and sublingual glands except (2EXT) or together with (3EXT) the parotid glands were extracted. At 16 days after the procedure, OUM was experimentally developed by topical acetic acid treatment on the labial fornix region of the inferior incisors, and the severity and bacterial loading level were evaluated. The salivary gland weights and histology were analyzed after administration of the representative anticancer drugs 5-fluorouracil or cisplatin.

RESULTS

The severity of OUM was greater in both the 3EXT and 2EXT rats and delayed the healing process compared with that in sham rats without salivary gland extraction. The healing process in the 3EXT rats was longer than that in the 2EXT rats. The number of colony-forming units in the ulcerative region from the 3EXT rats was 10-fold greater than that in the sham rats. Both 5-fluorouracil and cisplatin reduced glands weights and damaged the salivary glands.

CONCLUSIONS

These results suggest that chemotherapy-induced hyposalivation exacerbates OUM and delays healing, most likely due to loss of salivary clearance and antimicrobial functions. This study illustrates the significance of oral health care for cancer patients undergoing chemotherapy.

The nucleolus, an ally, and an enemy of cancer cells

The rates of ribosome production by a nucleolus and of protein biosynthesis by ribosomes are tightly correlated with the rate of cell growth and proliferation. All these processes must be matched and appropriately regulated to provide optimal cell functioning. Deregulation of certain factors, including oncogenes, controlling these processes, especially ribosome biosynthesis, can lead to cell transformation. Cancer cells are characterized by intense ribosome biosynthesis which is advantageous for their growth and proliferation. On the other hand, this feature can be engaged as an anticancer strategy. Numerous nucleolar factors such as nucleolar and ribosomal proteins as well as different RNAs, in addition to their role in ribosome biosynthesis, have other functions, including those associated with cancer biology. Some of them can contribute to cell transformation and cancer development. Others, under stress evoked by different factors which often hamper function of nucleoli and thus induce nucleolar/ribosomal stress, can participate in combating cancer cells. In this sense, intentional application of therapeutic agents affecting ribosome biosynthesis can cause either release of these molecules from nucleoli or their de novo biosynthesis to mediate the activation of pathways leading to elimination of harmful cells. This review underlines the role of a nucleolus not only as a ribosome constituting apparatus but also as a hub of both positive and negative control of cancer development. The article is mainly based on original papers concerning mechanisms in which the nucleolus is implicated directly or indirectly in processes associated with neoplasia.