Nephroprotective activities of quercetin with potential relevance to oxidative stress induced by valproic acid

Role of Nrf2/HO-1 and cytoglobin signaling in the protective effect of indole-3-acetic acid and chenodeoxycholic acid against kidney injury induced by valproate

Background

Purpose: Valproate (VPA) is an antiepileptic drug widely used to treat various psychiatric and neurological disorders. Although its use is generally considered safe, chronic administration may lead to kidney injury. The mechanisms underlying VPA kidney toxicity are not entirely explored. This has prompted our investigation into a novel molecular signaling pathway involved in VPA-induced kidney injury and the exploration of strategies to ameliorate this toxicity using indole-3-acetic acid (IAA) and chenodeoxycholic acid (CDCA).

Methods

Rats were divided as follows: group I (control); group II (VPA group), where rats were administered VPA (500 mg/kg, i.p.) daily to induce kidney injury for 3 weeks; and groups III and IV, where rats were orally treated with either IAA (40 mg/kg) or CDCA (90 mg/kg), respectively, 1h post-VPA dose, for 3 weeks. The effects of these compounds on kidney tissues were evaluated with a focus on their antioxidant and anti-inflammatory properties using biochemical, histopathological, and immunohistochemical analyses.

Results

VPA caused a significant reduction in renal glutathione (GSH) and heme oxygenase-1 (HO-1) levels, and superoxide dismutase (SOD) activity, along with a significant elevation in malondialdehyde (MDA) levels. Similarly, tumor necrosis factor-α (TNF-α), interleukin-1beta (IL-1β), and interleukin-6 (IL-6) levels were significantly increased. Immunohistochemical analysis demonstrated a significant decline in the immunoreactivity of nuclear factor erythroid 2-related factor (Nrf2) and cytoglobin antigens in renal cells. However, administration of either IAA or CDCA significantly ameliorated these altered parameters, including Nrf2/HO-1 and cytoglobin levels.

Conclusion

IAA and CDCA alleviated the kidney injury induced by VPA via downregulating the inflammatory response and upregulating the antioxidant capacity in renal tissue.

Ameliorative effects of Edaravone against Valproic Acid-Induced kidney damage

Valproic acid (VPA) is a well-known and increasingly documented antiepileptic drug that has been widely used in the treatment of epilepsy and/or epilepsy-related disorders. Prolonged clinical use of VPA has been reported to cause side effects such as nephrotoxicity. Edaravone (EDA) is a powerful free radical scavenger. The aim of the study was to investigate the protective effects of EDA against VPA-induced oxidative renal injury. Four experimental groups were formed by randomly assigning thirty-eight male Sprague Dawley rats. The first group, (Control Group, n = 8), consisted of healthy rats. The second group, (Group II, n = 10), comprised control rats given intraperitoneally EDA (30 mg/kg/day) for seven days. The third group (Group III, n = 10) was administered intraperitoneally only VPA (500 mg/kg/day) for seven days. The last group (Group IV, n = 10) was treated with VPA + EDA for seven days. On the 8th day, kidney tissues were immediately removed from rats. In kidney homogenates, reduced glutathione levels and Na/K+-ATPase, paraoxonase1 and prolidase activities were remarkably decreased while catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, myeloperoxidase, and xanthine oxidase activities and lipid peroxidation, protein carbonyl, advanced oxidized protein products, and hydroxyproline contents were notably elevated in VPA given group. Consistently, administration of EDA decreased renal degenerative changes seen in the kidney tissue of VPA given rats. Treatment with EDA in the VPA group significantly resulted in the recovery of both biochemical and histopathological alterations. As a result, EDA is potentially beneficial to revert oxidative renal damage induced by VPA.

Role of Plant Phytochemicals: Resveratrol, Curcumin, Luteolin and Quercetin in Demyelination, Neurodegeneration, and Epilepsy

Polyphenols are an important group of biologically active compounds present in almost all food sources of plant origin and are primarily known for their anti-inflammatory and antioxidative capabilities. Numerous studies have indicated their broad spectrum of pharmacological properties and correlations between their increased supply in the human diet and lower prevalence of various disorders. The positive effects of polyphenols application are mostly discussed in terms of cardiovascular system well-being. However, in recent years, they have also increasingly mentioned as prophylactic and therapeutic factors in the context of neurological diseases, being able to suppress the progression of such disorders and soothe accompanying symptoms. Among over 8000 various compounds, that have been identified, the most widely examined comprise resveratrol, curcumin, luteolin and quercetin. This review focuses on in vitro assessments, animal models and clinical trials, reflecting the most actual state of knowledge, of mentioned polyphenols' medicinal capabilities in epilepsy, demyelinating and neurodegenerative diseases of the central nervous system.

Quercetin prophylaxis protects the kidneys by modulating the renin-angiotensin-aldosterone axis under acute hypobaric hypoxic stress

The study presented here aims at assessing the effects of hypobaric hypoxia on RAAS pathway and its components along with mitigation of anomalies with quercetin prophylaxis. One hour prior to hypobaric hypoxia exposure, male SD rats were orally supplemented with quercetin (50 mg/kg BW) and acetazolamide (50 mg/kg BW) and exposed them to 25,000 ft. (7,620 m) in a simulated environmental chamber for 12 h at 25 ± 2 °C. Different biochemical parameters like renin activity, aldosterone, angiotensin I, ACE 2 were determined in plasma. As a conventional response to low oxygen conditions, oxidative stress parameters (ROS and MDA) were elevated along with suppressed antioxidant system (GPx and catalase) in plasma of rats. Quercetin prophylaxis significantly down regulated the hypoxia induced oxidative stress by reducing plasma ROS & MDA levels with efficient enhancement of antioxidants (GPx and Catalase). Further, hypoxia mediated regulation of renin and ACE 2 proves the outstanding efficacy of quercetin in repudiating altercations in RAAS cascade due to hypobaric hypoxia. Furthermore, differential protein expression of HIF-1α, NFκB, IL-18 and endothelin-1 analyzed by western blotting approves the biochemical outcomes and showed that quercetin significantly aids in the reduction of inflammation under hypoxia. Studies conducted with Surface Plasmon Resonance demonstrated a binding among quercetin and ACE 2 that indicates that this flavonoid might regulate RAAS pathway via ACE 2. Henceforth, the study promotes the prophylaxis of quercetin for the better adaptability under hypobaric hypoxic conditions via modulating the RAAS pathway.

Preclinical evidence of reno-protective effect of quercetin on acute kidney injury: a meta-analysis of animal studies

Objective: This study evaluated the reno-protective effects of quercetin in animal models of acute kidney injury (AKI). Methods: We conducted a systematic search of literature published before April 2023 in PubMed, Web of Science, and EMBASE databases. Methodological quality was assessed by SYRCLE's RoB tool. Funnel plot, Egger's test, and Begg's test were used to determine publication bias. Results: A total of 19 studies with 288 animals were included in this meta-analysis. The methodology quality scores of the included studies ranged from 4 to 7. The results indicated that quercetin reduced blood urea nitrogen (SMD = -4.78; 95% CI: 6.45, -3.12; p < 0.01; I2 = 84%) and serum creatinine (SMD: 2.73, 95% CI: 3.66, -1.80; p < 0.01; I2 = 80%) in AKI models. The result of sensitivity analysis was stable, while the results of funnel plot indicated asymmetric. In addition, we further analyzed inflammatory cytokines, oxidative stress levels, and kidney injury scores, and found that quercetin treatment had antioxidant and anti-inflammatory effects and improved kidney injury scores in animal models of AKI. Conclusion: Quercetin exhibited a promising reno-protective effect in AKI animal models. Systematic Review Registration: PROSPERO (CRD42023433333).

Combined effects of valproate and naringin on kidney antioxidative markers and serum parameters of kidney function in C57BL6 mice

Valproate is known to disturb the kidney function, and high doses or prolonged intake may cause serum ion imbalance, kidney tubular acidosis, proteinuria, hyperuricosuria, polyuria, polydipsia, and dehydration. The aim of this in vivo study was to see whether naringin would counter the adverse effects of high-dose valproate in C57Bl/6 mice and to which extent. As expected, valproate (150 mg/kg bw a day for 10 days) caused serum hyperkalaemia, more in male than female mice. Naringin reversed (25 mg/kg bw a day for 10 days) the hyperkalaemia and activated antioxidative defence mechanisms (mainly catalase and glutathione), again more efficiently in females. In males naringin combined with valproate was not as effective and even showed some prooxidative effects.

Assessment of Protective Effects of Carvacrol on Haloperidol-Induced Oxidative Stress and Genotoxicity in Human Peripheral Blood Lymphocytes

Haloperidol is a first-generation antipsychotic drug that has several indications in a wide range of mental conditions. The extensive prescription of haloperidol is correlated with some less-known adverse effects such as genotoxicity. Carvacrol is a monoterpenoid mainly found in oregano and thyme. It has the potential to scavenge free radicals in addition to increasing antioxidant defense enzyme activities and glutathione levels. In this study, we attempted to explore the possible potential of haloperidol in inducing genotoxicity in human peripheral lymphocytes as well as the protective role of carvacrol against this effect. The lymphocytes were divided into separate groups as follows: control group (cosolvent and NS); carvacrol group (5 μM); haloperidol group (25, 50, and 100 ng/ml); haloperidol (25, 50, and 100 ng/ml) + carvacrol (5 μM); positive control (0.8 μg/ml Cisplatin). After 24 hours of treatment, we conducted a cytokinesis-Block micronucleus test and an alkaline comet assay in order to determine genetic damage. Additionally, we measured glutathione and MDA levels as the biomarkers associated with oxidative stress. Significant increases in the levels of genotoxicity biomarkers (micronucleus frequency, DNA percentage in tail and tail moment) were observed in haloperidol-treated cells. The result of our oxidative stress tests also demonstrated that haloperidol had the potential to induce oxidative stress via reducing the levels of glutathione and increasing lipid peroxidation. Treatment with carvacrol significantly decreased the genotoxic events. It can be presumed that the induction of oxidative stress by haloperidol is the critical event associated with haloperidol-mediated genotoxicity. Therefore, using carvacrol as a natural antioxidant protected human lymphocytes against haloperidol genetic damage.

A review: Systematic research approach on toxicity model of liver and kidney in laboratory animals

Therapeutic experiments are commonly performed on laboratory animals to investigate the possible mechanism(s) of action of toxic agents as well as drugs or substances under consideration. The use of toxins in laboratory animal models, including rats, is intended to cause toxicity. This study aimed to investigate different models of hepatotoxicity and nephrotoxicity in laboratory animals to help researchers advance their research goals. The current narrative review used databases such as Medline, Web of Science, Scopus, and Embase and appropriate keywords until June 2021. Nephrotoxicity and hepatotoxicity models derived from some toxic agents such as cisplatin, acetaminophen, doxorubicin, some anticancer drugs, and other materials through various signaling pathways are investigated. To understand the models of renal or hepatotoxicity in laboratory animals, we have provided a list of toxic agents and their toxicity procedures in this review.

Protective effect of quercetin on kidney diseases: From chemistry to herbal medicines

Kidney injuries may trigger renal fibrosis and lead to chronic kidney disease (CKD), but effective therapeutic strategies are still limited. Quercetin is a natural flavonoid widely distributed in herbal medicines. A large number of studies have demonstrated that quercetin may protect kidneys by alleviating renal toxicity, apoptosis, fibrosis and inflammation in a variety of kidney diseases. Therefore, quercetin could be one of the promising drugs in the treatment of renal disorders. In the present study, we review the latest progress and highlight the beneficial role of quercetin in kidney diseases and its underlying mechanisms. The pharmacokinetics and bioavailability of quercetin and its proportion in herbal medicine will also be discussed.

Effects of naringin and valproate interaction on liver steatosis and dyslipidaemia parameters in male C57BL6 mice

Valproate is a common antiepileptic drug whose adverse effects include liver steatosis and dyslipidaemia. The aim of our study was to see how natural flavonoid antioxidant naringin would interact with valproate and attenuate these adverse effects. For this reason we treated male C57BL6 mice with a combination of 150 mg/kg of valproate and 25 mg/kg naringin every day for 10 days and compared their serum triglycerides, cholesterol, LDL, HDL, VLDL, and liver PPAR-alpha, PGC-1 alpha, ACOX1, Nrf2, SOD, CAT, GSH, and histological signs of steatosis. Valproate increased lipid peroxidation parameters and caused pronounced microvesicular steatosis throughout the hepatic lobule in all acinar zones, but naringin co-administration limited steatosis to the lobule periphery. In addition, it nearly restored total serum cholesterol, LDL, and triglycerides and liver ACOX1 and MDA to control levels. and upregulated PPAR-alpha and PGC-1 alpha, otherwise severely downregulated by valproate. It also increased SOD activity. All these findings suggest that naringin modulates key lipid metabolism regulators and should further be investigated in this model, either alone or combined with other lipid regulating drugs or molecules.

Neuropharmacological Effects of Quercetin: A Literature-Based Review

Quercetin (QUR) is a natural bioactive flavonoid that has been lately very studied for its beneficial properties in many pathologies. Its neuroprotective effects have been demonstrated in many in vitro studies, as well as in vivo animal experiments and human trials. QUR protects the organism against neurotoxic chemicals and also can prevent the evolution and development of neuronal injury and neurodegeneration. The present work aimed to summarize the literature about the neuroprotective effect of QUR using known database sources. Besides, this review focuses on the assessment of the potential utilization of QUR as a complementary or alternative medicine for preventing and treating neurodegenerative diseases. An up-to-date search was conducted in PubMed, Science Direct and Google Scholar for published work dealing with the neuroprotective effects of QUR against neurotoxic chemicals or in neuronal injury, and in the treatment of neurodegenerative diseases. Findings suggest that QUR possess neuropharmacological protective effects in neurodegenerative brain disorders such as Alzheimer’s disease, Amyloid β peptide, Parkinson’s disease, Huntington's disease, multiple sclerosis, and amyotrophic lateral sclerosis. In summary, this review emphasizes the neuroprotective effects of QUR and its advantages in being used in complementary medicine for the prevention and treatment o of different neurodegenerative diseases.

Nephroprotective potential of Anogeissus latifolia Roxb. (Dhava) against gentamicin-induced nephrotoxicity in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Stem bark of Anogeissus latifolia Roxb. (Family: Combretaceae) is used traditionally and ethnomedicinally for correction of kidney disorders.

AIM OF THE STUDY

The present study demonstrates the nephroprotective potential of stem bark of A. latifolia Roxb.

MATERIALS AND METHODS

The HPTLC fingerprint and HPLC analysis were carried out to standardize the ethanolic extract of stem bark of A. latifolia (ALEE) using ellagic acid as a marker. Nephrotoxicity was induced in adult Wistar albino rats by gentamicin (100 mg/kg, intraperitoneally for 8 days) and they were treated with ALEE (100, 200 and 400 mg/kg, orally for 8 days), ellagic acid (10 mg/kg, orally for 8 days) and cystone syrup (5 ml/kg, orally), a standard reference a polyherbal formulation. Urine volume, serum and urine levels of creatinine, urea and uric acid, oxidative stress parameters (lipid peroxidation, catalase, superoxide dismutase and reduced glutathione), inflammatory markers (TNF-α and IL-6) and kidney weight along with its histological changes were studied in experimental animals.

RESULTS

HPTLC, HPLC and LC-MS analysis of ALEE revealed the presence of ellagic acid and other various phytoconstituents. Administration of gentamicin caused significant increase in urine output and kidney weight, elevated biochemical, inflammatory and oxidative stress parameters as well as caused histological damage in the kidney tissue. These parameters were attenuated by the concurrent treatment with ALEE and ellagic acid. The effects were comparable to cystone.

CONCLUSION

Present investigations concluded that ALEE exhibited nephroprotective potential and validated the traditional use of stem bark of A. latifolia in kidney disorders. The nephroprotective effect may be attributed to the antioxidant and anti-inflammatory phytoconstituents in ALEE.

Phytochemical add-on therapy to DMARDs therapy in rheumatoid arthritis: In vitro and in vivo bases, clinical evidence and future trends

The use of biologically active compounds derived from plants i.e. phytochemicals, have been known for ages for their pharmacological activities in the treatment of autoimmune disorders like rheumatoid arthritis (RA). Besides enormous scientific evidence, the therapeutic potential of phytochemicals is often undervalued. The treatment in RA involves the use of synthetic and biological disease modifying anti-rheumatic drugs (DMARDs). However, the long-term treatment in RA is associated with the risk of gastrointestinal, liver, pulmonary and renal toxicities and serious infections including latent tuberculosis, pneumococcus influenza, herpes zoster and hepatitis. These adverse effects sometimes lead to discontinuation of the therapy. A relatively new vision based on the combination of DMARDs with phytochemicals exhibiting anti-inflammatory, anti-arthritic, anti-oxidant, hepatoprotective and nephroprotective properties for the treatment of RA has achieved substantial importance in the last decade. From this perspective, the present review focuses on the combination of DMARDs (primarily MTX) with phytochemicals that have shown synergistic therapeutic effects while decreasing the toxic repercussions of current RA therapy. The review covers recent evidences of such combination studies that have shown promising results both in experimental arthritic models and clinical arthritis. Few of the combinations including resveratrol, sinomenine, coenzyme Q10 exhibited considerable interest because of their efficacy as an adjuvant to the MTX/standard DMARDs therapy in clinical trials. Besides giving an overview of such combination studies the review also critically discusses the limitations with the use of phytochemicals (e.g. solubility, permeability and bioavailability) compromising their clinical application. Additionally, it stresses upon the need of novel delivery systems and pharmaceutical technologies to increase the therapeutic efficacy of the combination therapy. Overall, the review unveils the potential of phytochemicals in combination with DMARDs with increased tolerability and superior efficacy in further refining the future of the RA therapy.

Spatiotemporal evaluation of the mouse embryonic redox environment and histiotrophic nutrition following treatment with valproic acid and 1,2-dithiole-3-thione during early organogenesis

Redox regulation during metazoan development ensures that coordinated metabolic reprogramming and developmental signaling are orchestrated with high fidelity in the hypoxic embryonic environment. Valproic acid (VPA), an anti-seizure medication, is known to increase markers of oxidation and also increase the risk of neural tube defects (NTDs) when taken during pregnancy. It is unknown, however, whether oxidation plays a direct role in failed neural tube closure (NTC). Spatial and temporal fluctuations in total glutathione (GSH) and total cysteine (Cys) redox steady states were seen during a 24 h period of CD-1 mouse organogenesis in untreated conceptuses and following exposure to VPA and the Nrf2 antioxidant pathway inducer, 1,2-dithiole-3-thione (D3T). Glutathione, glutathione disulfide (GSSG), and Cys, cystine (CySS) concentrations, measured in conceptal tissues (embryo/visceral yolk sac) and fluids (yolk sac fluid/amniotic fluid) showed that VPA did not cause extensive and prolonged oxidation during the period of NTC, but instead produced transient periods of oxidation, as assessed by GSH:GSSG redox potentials, which revealed oxidation in all four conceptal compartments at 4, 10, and 14 h, corresponding to the period of heartbeat activation and NTC. Other changes were tissue and time specific. VPA treatment also reduced total FITC-Ab clearance from the medium over 3 h, indicating potential disruption of nutritive amino acid supply. Overall, these results indicated that VPA's ability to affect cellular redox status may be limited to tissue-specific windows of sensitivity during the period of NTC. The safety evaluation of drugs used during pregnancy should consider time and tissue specific redox factors.

Quercetin-loaded F127 nanomicelles: Antioxidant activity and protection against renal injury induced by gentamicin in rats

Quercetin (Q) is formulated into oil-in-water F127 microemulsions to improve its bioavailability. The size of the Q-loaded microemulsions system was about 8 nm by dynamic light scattering analysis. To compare antioxidant activity of bulk solution and microemulsion of Q, free radical scavenging activity was evaluated against 2,2-diphenyl-1-picrylhydrazyl (DPPH). The IC50 values were 56.77 and 187.68 μM, respectively. The drug in the bulk form released 16.34 times faster than microemulsion form. Although gentamicin (GM) has potent efficacy against gram-negative bacteria, it induces renal toxicity. Poor solubility and low bioavailability of Q as a bioflavonoid with potent antioxidant activity, limit its therapeutic application. We aimed to compare the effect of free Q and nanoencapsulated (NEQ) against GM-induced renal damage in Wistar rats. Forty-two animals were divided into six groups. Control and GM groups received apo-nanomicelles and GM (100 mg/kg) for 10 days. Two groups received Q (50 mg/kg, i.g.) and NEQ (50 mg/kg, i.g.) respectively for 10 days. Remaining two groups received Q and NEQ (50 mg/kg, i.g.) plus GM (100 mg/kg, i.p.) simultaneously for 10 days. After the experiments, serum and kidneys were used for biochemical, molecular and histological examinations. Immunohistochemical analysis was performed to explore kidney injury molecule-1 (KIM-1) expression as a specific protein biomarker of renal injury. Our findings indicated oxidative stress and altered histological features in renal tissue with deviated serum renal biomarkers in GM-treated rats. Although Q treatment in GM group tried to protect against GM-induced nephrotoxicity, but there were still differences compared to control rats. However, NEQ administration corrected elevations in the levels of urea, creatinine, uric acid and decrements in serum total proteins of GM group. Meanwhile, NEQ restored renal oxidative injury in GM rats through attenuation of lipid peroxidation and enhancement of antioxidant defense systems, glutathione, catalase and superoxide dismutase. NEQ could also normalize GM-induced abnormal renal histology features including fibrosis. Furthermore, the result of immunohistochemistry study confirmed these findings by undetecting KIM-1 expression in NEQ treated GM group, meanwhile showing this renal biomarker in GM and Q treated GM groups. Therefore, NEQ seems to be useful in protecting against renal oxidative stress and kidney damage in a rat model of GM nephrotoxicity which deserve further evaluations.

Mechanistic Aspects and Therapeutic Potential of Quercetin against COVID-19-Associated Acute Kidney Injury

The inflammatory mediator and oxidant agent storm caused by the SARS-CoV-2 infection has been strongly associated with the failure of vital organs observed in critically ill patients with coronavirus disease 2019 (COVID-19) and the death of thousands of infected people around the world. Acute kidney injury (AKI) is a common renal disorder characterized by a sudden and sustained decrease in renal function with a critical influence on poor prognosis and lethal clinical outcomes of various etiologies, including some viral infection diseases. It is known that oxidative stress and inflammation play key roles in the pathogenesis and development of AKI. Quercetin is a natural substance that has multiple pharmacological properties, such as anti-inflammatory action, and is used as a dietary supplement. There is evidence of the anti-coronavirus activities of this compound, including against the target SARS-CoV-2 3CLpro. The ability to inhibit coronavirus and its inflammatory processes is strongly desired in a new drug for the treatment of COVID-19. Therefore, in this review, the dual effect of quercetin is discussed from a mechanistic perspective in relation to AKI kidney injury and its nephroprotective potential to SARS-CoV-2 patients.

Punica granatum improves renal function in gentamicin-induced nephropathy in rats via attenuation of oxidative stress

BACKGROUND

Gentamicin is widely used as an antibiotic for the treatment of gram negative infections. Evidences indicates that oxidative stress is involved in gentamicin-induced nephrotoxicity. In Ayurvedic medicine, Punica granatum Linn. is considered as 'a pharmacy unto itself". It has been claimed in traditional literature, to treat various kidney ailments due to its antioxidant potential.

OBJECTIVE

To explore the possible mechanism of action of methanolic extract of P.granatum leaves (MPGL) in exerting a protective effect on gentamicin-induced nephropathy.

MATERIAL AND METHODS

Animals were administered with gentamicin (80 mg/kg/day i.m.) and simultaneously with MPGL (100, 200 and 400 mg/kg p.o.) or metformin (100 mg/kg p.o.) for 8 days. A satellite group was employed in order to check for reversibility of nephrotoxic effects post discontinuation of gentamicin administration. At the end of the study, all the rats were sacrificed and serum-urine parameters were investigated. Antioxidant enzymes and tumor necrosis factor alpha (TNF-α) levels were determined in the kidney tissues along with histopathological examination of kidneys.

RESULTS

Increase in serum creatinine, urea, TNF-α, lipid peroxidation along with fall in the antioxidant enzymes activity and degeneration of tubules, arterioles as revealed by histopathological examination confirmed the manifestation of nephrotoxicity caused due to gentamicin. Simultaneous administration of MPGL and gentamicin protected kidneys against nephrotoxic effects of gentamicin as evidenced from normalization of renal function parameters and amelioration of histopathological changes.

CONCLUSION

Data suggests that MPGL attenuated oxidative stress associated renal injury by preserving antioxidant enzymes, reducing lipid peroxidation and inhibiting inflammatory mediators such as TNF-α.

Dose-Dependent Behavioral and Antioxidant Effects of Quercetin and Methanolic and Acetonic Extracts from Heterotheca inuloides on Several Rat Tissues following Kainic Acid-Induced Status Epilepticus

Kainic acid (KA) has been used to study the neurotoxicity induced after status epilepticus (SE) due to activation of excitatory amino acids with neuronal damage. Medicinal plants can protect against damage caused by KA-induced SE; in particular, organic extracts of Heterotheca inuloides and its metabolite quercetin display antioxidant activity and act as hepatoprotective agents. However, it is unknown whether these properties can protect against the hyperexcitability underlying the damage caused by KA-induced SE. Our aim was to study the protective effects (with regard to behavior and antioxidant activity) of administration of natural products methanolic (ME) and acetonic (AE) extracts and quercetin (Q) from H. inuloides at doses of 30 mg/kg (ME30, AE30, and Q30 groups), 100 mg/kg (ME100, AE100, and Q100 groups), and 300 mg/kg (ME300, AE300, and Q300 groups) against damage in brain regions of male Wistar rats treated with KA. We found dose-dependent effects on behavioral and biochemical studies in the all-natural product groups vs. the control group, with decreases in seizure severity (Racine's scale) and increases in seizure latency (p < 0.05 in the ME100, AE100, Q100, and Q300 groups and p < 0.01 in the AE300 and ME300 groups); on lipid peroxidation and carbonylated proteins in all brain tissues (p < 0.0001); and on GPx, GR, CAT, and SOD activities with all the treatments vs. KA (p ≤ 0.001). In addition, there were strong negative correlations between carbonyl levels and latency in the group treated with KA and in the group treated with methanolic extract in the presence of KA (r = ‐0.9919, p = 0.0084). This evidence suggests that organic extracts and quercetin from H. inuloides exert anticonvulsant effects via direct scavenging of reactive oxygen species (ROS) and modulation of antioxidant enzyme activity.

The footprints of mitochondrial impairment and cellular energy crisis in the pathogenesis of xenobiotics-induced nephrotoxicity, serum electrolytes imbalance, and Fanconi's syndrome: A comprehensive review

Fanconi's Syndrome (FS) is a disorder characterized by impaired renal proximal tubule function. FS is associated with a vast defect in the renal reabsorption of several chemicals. Inherited and/or acquired conditions seem to be connected with FS. Several xenobiotics including many pharmaceuticals are capable of inducing FS and nephrotoxicity. Although the pathological state of FS is well described, the exact underlying etiology and cellular mechanism(s) of xenobiotics-induced nephrotoxicity, serum electrolytes imbalance, and FS are not elucidated. Constant and high dependence of the renal reabsorption process to energy (ATP) makes mitochondrial dysfunction as a pivotal mechanism which could be involved in the pathogenesis of FS. The current review focuses on the footprints of mitochondrial impairment in the etiology of xenobiotics-induced FS. Moreover, the importance of mitochondria protecting agents and their preventive/therapeutic capability against FS is highlighted. The information collected in this review may provide significant clues to new therapeutic interventions aimed at minimizing xenobiotics-induced renal injury, serum electrolytes imbalance, and FS.

Mechanism of valproic acid-induced Fanconi syndrome involves mitochondrial dysfunction and oxidative stress in rat kidney

AIM

Drug-induced kidney proximal tubular injury and renal failure (Fanconi syndrome; FS) is a clinical complication. Valproic acid (VPA) is among the FS-inducing drugs. The current investigation was designed to evaluate the role of mitochondrial dysfunction and oxidative stress in VPA-induced renal injury.

METHODS

Animals received VPA (250 and 500 mg/kg, i.p., 15 consecutive days). Serum biomarkers of kidney injury and markers of oxidative stress were assessed. Moreover, kidney mitochondria were isolated and mitochondrial indices, including succinate dehydrogenase activity (SDA), mitochondrial depolarization, mitochondrial permeability transition pore (MPP), reactive oxygen species (ROS), lipid peroxidation (LPO), mitochondrial glutathione, and ATP were determined.

RESULTS

Valproic acid-treated animals developed biochemical evidence of FS as judged by elevated serum gamma-glutamyl transferase (γ-GT), alkaline phosphatase (ALP), creatinine (Cr), and blood urea nitrogen (BUN) along with hypokalaemia, hypophosphataemia, and a decrease in serum uric acid. VPA caused an increase in kidney ROS and LPO. Renal GSH reservoirs were depleted and tissue antioxidant capacity decreased in VPA-treated animals. Renal tubular interstitial nephritis, tissue necrosis, and atrophy were also evident in VPA-treated rats. Mitochondrial parameters including SDA, MMP, GSH, ATP and MPP were decreased and mitochondrial ROS and LPO were increased with VPA treatment. It was found that carnitine (100 mg/kg, i.p.) mitigated VPA adverse effects towards the kidney.

CONCLUSIONS

These data suggest that mitochondrial dysfunction and oxidative stress contributed to the VPA-induced FS. On the other hand, carnitine could be considered a potentially safe and effective therapeutic option in attenuating VPA-induced renal injury.

Renal dysfunctions/injury in adult epilepsy patients treated with carbamazepine or valproate

OBJECTIVES

Clinical and subclinical laboratory evidence of renal proximal tubular dysfunction had been reported in children with epilepsy as an adverse effect of some antiepileptic drugs (AEDs). This study aimed to determine kidney function in adult patients with monosymptomatic epilepsy of unknown etiology and treated with valproate (VPA) or carbamazepine (CBZ).

METHODS

This study included 60 patients [mean age of 33.97 ± 6.70 years and treated with VPA (n = 24) or CBZ (n = 36) for mean duration of treatment of 6.03 ± 2.81years. Measurements of serum creatinine (sCr), urinary creatinine, creatinine clearance (CrCl) and serum kidney injury molecule 1 (KIM-1), markers of renal dysfunction/injury were done.

RESULTS

Compared to controls, patients had higher sCr, KIM-1 and lower CrCl levels. Compared to patients on VPA, those on CBZ had relatively higher KIM-1 and lower CrCl levels. We reported only significant correlations between KIM-1 with sCr (r = 0.324, p = 0.001) and duration of treatment with AEDs (r = 0.301, p = 0.02).

CONCLUSION

Chronic VPA and CBZ therapy may be associated with subclinical renal glomerular and/or proximal tubular dysfunctions or injuries. The treating neurologist have to consider this while selection of AED on start treating patients or modifying the AED for patients at high risk of kidney injury.

The effect of antiepileptic drugs on the kidney function and structure

Long-term use of antiepileptic drugs (AEDs) is associated with number of somatic conditions. Data from experimental, cross-sectional and prospective studies have evidence for the deleterious effect of some AEDs on the kidney. Areas covered: This review summarized the current knowledge of the effect of AEDs on the kidney including evidence and mechanisms. Fanconi syndrome was reported with valproate (VPA) therapy in severely disabled children with epilepsy. Renal tubular acidosis and urolithiasis were reported with acetazolamide, topirmate and zonisamide, drugs with carbonic anhydrase inhibition properties. Increased levels of urinary N-acetyl-beta-D-glucosaminidase (NAG) to urinary creatinine (U-NAG/UCr), urinary excretion of α1-micrglobulin, β-galactosidase activity; and urinary malondialdehyde to creatinine (MDA/Cr), markers of renal glomerular and tubular injury, were reported with chronic use of some AEDs (VPA, carbamazepine and phenytoin). The mechanism(s) of kidney dysfunction/injury induced by AEDs is unknown. Experimental and clinical studies have shown that VPA induces oxidative stress, mitochondrial deficits, carnitine deficiency and inflammation and fibrosis in renal tissue in mice and in vitro studies. Expert commentary: It seems reasonable to monitor kidney function during treating patients with epilepsy at high risk of kidney injury (e.g. on combined therapy with more than one AED, severely disabled children, etc).

Phytanic acid induced neurological alterations in rat brain synaptosomes and its attenuation by melatonin

Phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) (Phyt) is a saturated branched chain fatty acid which originates after the breakdown of chlorophyll molecule, phytol. It plays an important role in a variety of metabolic disorders with peroxisomal impairments. The aim of our investigation was to evaluate the adverse effects of Phyt on synaptic functions by using synaptosomal preparation of rat brain as an in vitro model and the possible protective role of melatonin against Phyt-induced neurotoxicity. Melatonin is an antioxidant, secreted by the pineal gland. Melatonin and its metabolites have neuroprotective effects on cellular stress, by reducing reactive oxygen species (ROS) and reactive nitrogen species (RNS). In the present investigation, synaptosomes prepared from rat brain were co-treated with melatonin (10μM) and Phyt (50μM) for 2h. Co-treatment of Phyt with melatonin significantly restored the altered levels of protein carbonyl (PC) contents and lipid peroxidation (LPO). It also replenished the Phyt-induced alterations on the levels of non-enzymatic antioxidant defence reduced glutathione (GSH), enzymatic antioxidants such as catalase (CAT) and superoxide dismutase (SOD) and synaptosomal integral enzymes such as AChE, Na⁺, K⁺-ATPase and MAO. We observed that Phyt induced oxidative stress in synaptosomes as indicated by an elevation in the generation of ROS and melatonin was able to inhibit the elevated ROS generation. Moreover, the neurotoxic effects elicited by Phyt on NO level and membrane potential were totally prevented by the treatment of melatonin. The results of our investigation emphasize the potential use of melatonin as a nutraceutical and mitigatory agent against Phyt-induced oxidative stress.

Quercetin Attenuates Vascular Calcification through Suppressed Oxidative Stress in Adenine-Induced Chronic Renal Failure Rats

Background

This study investigated whether quercetin could alleviate vascular calcification in experimental chronic renal failure rats induced by adenine.

Methods

32 adult male Wistar rats were randomly divided into 4 groups fed normal diet, normal diet with quercetin supplementation (25 mg/kg·BW/d), 0.75% adenine diet, or adenine diet with quercetin supplementation. All rats were sacrificed after 6 weeks of intervention. Serum renal functions biomarkers and oxidative stress biomarkers were measured and status of vascular calcification in aorta was assessed. Furthermore, the induced nitric oxide synthase (iNOS)/p38 mitogen activated protein kinase (p38MAPK) pathway was determined to explore the potential mechanism.

Results

Adenine successfully induced renal failure and vascular calcification in rat model. Quercetin supplementation reversed unfavorable changes of phosphorous, uric acid (UA) and creatinine levels, malonaldehyde (MDA) content, and superoxide dismutase (SOD) activity in serum and the increases of calcium and alkaline phosphatase (ALP) activity in the aorta (P < 0.05) and attenuated calcification and calcium accumulation in the medial layer of vasculature in histopathology. Western blot analysis showed that iNOS/p38MAPK pathway was normalized by the quercetin supplementation.

Conclusions

Quercetin exerted a protective effect on vascular calcification in adenine-induced chronic renal failure rats, possibly through the modulation of oxidative stress and iNOs/p38MAPK pathway.

Protective effects of fennel oil extract against sodium valproate-induced hepatorenal damage in albino rats

Foeniculum vulgare (Apiaceae) is commonly known as fennel. This herb is well-known worldwide and traditionally used as curative herbal therapy for the treatment of epileptic disease, seizurescarminative, digestive, lactogogue, diuretic, treating respiratory and gastrointestinal disorders. The aim of present study is to investigate the possible effect of fennel oil against the toxicity of Sodium-Valproic (SVP) in albino rats. In order to assess the protection of fennel oil on SVP induced hepato- and nephro-toxicity, male albino rats were treated with 1 ml/kg b.w fennel oil 3 days/week for 6 weeks. The biochemical analyses of hepatic enzymes were evaluated by estimating blood biomarkers of liver and renal damage along with histological examination. The results obtained from this work showed that treating animals with SVP lead to many histopathological alterations in the liver and kidney tissues. The effect appeared in the liver tissue include leukocyte infiltrations, cytoplasmic vacuolization of the hepatocytes, fatty degeneration and congestion of blood vessels. This commonly used chemical (SVP) caused some unwanted effects on the kidney cortex which histologically observed as degeneration in renal tubules, atrophy of the glomeruli and edema. Biochemical results also revealed an abnormal increase in the enzyme level of AST, SAT, ALP, bilirubin, creatinine and urea-nitrogen, with a noticed decrease in total protein content. However, the results of treated rats with SVP plus fennel oil showed some positive histopathological changes in both the liver and kidney tissues. These results have confirmed that fennel oil has positive effects on the histological structure of the liver and kidney and the biochemical levels of AST, ALT, ALP, bilirubin, total proteins, creatinine and urea. It is concluded that fennel oil has various pharmacological properties including antioxidant, anti-cancer activity, anti-inflammatory. These valuable effects might be due to the presence of aromatic compounds trans-anethole. This useful properties of fennel plant could be due to its antioxidant activity that prevents the toxicity of SVP.

The effects of quercetin on the gene expression of the GABAA receptor α5 subunit gene in a mouse model of kainic acid-induced seizure

The flavonoid quercetin has recently been reported to have neuroprotective effects, and the role of the gamma-aminobutyric acid A alpha 5 subunit (GABAA α5) receptor has been determined in some nervous system disorders. The aim of this study was to identify the molecular mechanism of the effect of quercetin administered at anticonvulsive doses on the expression of the GABAA α5 receptor gene in kainic acid (KA)-induced seizures in mice. The experimental animals were divided into four groups: control, KA, and KA + quercetin at 50 or 100 mg/kg, respectively. The results showed a dose-dependent reduction in the behavioral seizure score with quercetin pre-treatment in the KA mouse model. Two hours after the end of the 7-day treatment regimen, expression of the GABAA α5 receptor gene in the hippocampus was found to be increased in the KA group, but this increase was reduced in the KA + quercetin 50 or 100 mg/kg treatment groups. These results suggest that expression of the GABAA α5 receptor could be a mechanism for reducing seizure severity or may be a marker of seizure severity. Further studies are necessary to clarify quercetin's mechanism of action and the relation of GABAA α5 receptor gene expression to seizure severity.

Effects of quercetin on methotrexate-induced nephrotoxicity in rats

OBJECTIVE

This experimental study was conducted to elucidate the possible protective/therapeutic effects of quercetin against methotrexate (Mtx)-induced kidney toxicity with biochemical and histopathological studies.

METHODS

Twenty-four adult male rats were randomly divided into four groups, as follows: control group (saline intraperitoneally (i.p.), 9 days), Mtx group (20 mg/kg i.p., single dose), Mtx + quercetin group (50 mg/kg quercetin was orally administered 2 days before and 6 days after Mtx administration) and only quercetin group (50 mg/kg oral, 9 days). Structural changes were evaluated by hematoxylin-eosin and periodic acid-Schiff stainings. Apoptotic changes were investigated by terminal deoxynucleotidyl transferase dUTP nick end labeling assay and caspase-3 antibody. Superoxide dismutase (SOD) and malondialdehyde (MDA) levels were measured in tissue and plasma samples.

RESULTS

Mtx compared with the control group, there was significant increase in nephrotoxic tissue damage findings, in addition to apoptotic index (APOI) and caspase-3 expression ( p < 0.05). Mtx + quercetin group revealed significantly lower histopathological damage and APOI and caspase-3 expression decreased when compared to Mtx group. MDA levels were increased in Mtx group compared to others, and by the use of quercetin, this increase was significantly reduced. SOD levels were higher in Mtx group than others. This increase was evaluated as a relative increase arising from oxidative damage caused by Mtx.

CONCLUSION

As a result, Mtx administration may involve oxidative stress by causing structural and functional damage in kidney tissue in rats. Quercetin reduced the Mtx-induced oxidative stress through its antioxidant properties and so quercetin may be promising to alleviate Mtx-induced renal toxicity.

Multi-target detection of oxidative stress biomarkers in quercetin and myricetin treated human red blood cells

Quercetin and myricetin help against oxidative stress in human red blood cells during aging, thereby has tremendous scope in medical diagnostics and therapeutics.

Quercetin ameliorates methotrexate-induced renal damage, apoptosis and oxidative stress in rats

BACKGROUND

In the present study, the protective and therapeutic effects of quercetin (QE) on renal injury induced by methotrexate (MTX) have been examined.

MATERIALS AND METHODS

A total of 24 male rats were divided into the following three groups: control group, MTX group, and MTX + QE group. Rats in MTX group received 20 mg/kg of single dose of MTX, while those in MTX + QE group received 20 mg/kg of single dose MTX, in addition to 15 mg/kg of QE administered 30 min prior to MTX and in the following 5-day period as a single daily dose. At the end of the experimental period, renal tissues were removed for histopathological and biochemical assessments.

RESULTS

Light microscopic examination showed a disruption of the renal structure in rats in MTX group in the form of tubular degeneration and dilation, with shedding of the tubular epithelial cells into the lumen. QE treatment was associated with less marked degenerative changes, with a similar histological appearance to that of controls. Furthermore, QE treatment resulted in decreased the number of apoptotic cells. Biochemical assessments showed significantly higher malondialdehyde (MDA) levels in MTX group as compared to control and MTX + QE groups. superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) levels showed a significant decrease in MTX group as compared to controls. However, QE significantly suppressed MDA level, compensated deficits in the anti-oxidant defenses [reduced SOD, GSH-Px, and CAT levels] in kidney tissue resulted from MTX administration.

CONCLUSIONS

In conclusion, renal toxic effects of MTX may be alleviated by QE.