Quercetin attenuates cisplatin-induced ovarian toxicity in rats: Emphasis on anti-oxidant, anti-inflammatory and anti-apoptotic activities

Gynotoxic Effects of Chemotherapy and Potential Protective Mechanisms

Chemotherapy is one of the leading cancer treatments. Unfortunately, its use can contribute to several side effects, including gynotoxic effects in women. Ovarian reserve suppression and estrogen deficiency result in reduced quality of life for cancer patients and are frequently the cause of infertility and early menopause. Classic alkylating cytostatics are among the most toxic chemotherapeutics in this regard. They cause DNA damage in ovarian follicles and the cells they contain, and they can also induce oxidative stress or affect numerous signaling pathways. In vitro tests, animal models, and a few studies among women have investigated the effects of various agents on the protection of the ovarian reserve during classic chemotherapy. In this review article, we focused on the possible beneficial effects of selected hormones (anti-Müllerian hormone, ghrelin, luteinizing hormone, melatonin), agents affecting the activity of apoptotic pathways and modulating gene expression (C1P, S1P, microRNA), and several natural (quercetin, rapamycin, resveratrol) and synthetic compounds (bortezomib, dexrazoxane, goserelin, gonadoliberin analogs, imatinib, metformin, tamoxifen) in preventing gynotoxic effects induced by commonly used cytostatics. The presented line of research appears to provide a promising strategy for protecting and/or improving the ovarian reserve in the studied group of cancer patients. However, well-designed clinical trials are needed to unequivocally assess the effects of these agents on improving hormonal function and fertility in women treated with ovotoxic anticancer drugs.

Donepezil and quercetin alleviate valproate-induced testicular oxidative stress, inflammation and apoptosis: Imperative roles of AMPK/SIRT1/ PGC-1α and p38-MAPK/NF-κB/ IL-1β signaling cascades

The mounting evidence of valproate-induced testicular damage in clinical settings is alarming, especially for men taking valproate (VPA) for long-term or at high doses. Both donepezil (DON) and quercetin (QUE) have promising antioxidant, anti-inflammatory, and anti-apoptotic effects. Therefore, this study aimed to determine whether DON, QUE, and their combination could mitigate VPA-induced testicular toxicity and unravel the mechanisms underlying their protective effect. In this study, male albino rats were randomly categorized into six equal groups: control, VPA (500 mg/kg, I.P., for 14 days), DON (3 and 5 mg/kg), QUE (50 mg/kg), and DON 3 + QUE combination groups. The DON and QUE treatments were administered orally for 7 consecutive days before VPA administration and then concomitantly with VPA for 14 days. VPA administration disrupted testicular function by altering testicular architecture, ultrastructure, reducing sperm count, viability, and serum testosterone levels. Additionally, VPA triggered oxidative damage, inflammatory, and apoptotic processes and suppressed the AMPK/SIRT1/PGC-1α signaling cascade. Pretreatment with DON, QUE, and their combination significantly alleviated histological and ultrastructure damage caused by VPA and increased the serum testosterone level, sperm count, and viability. They also suppressed the oxidative stress by reducing testicular MDA content and elevating SOD activity. In addition, they reduced the inflammatory response by suppressing IL-1β level, NF-κB, and the p38-MAPK expression as well as inhibiting apoptosis by diminishing caspase-3 and increasing Bcl-2 expression. These novel protective effects were mediated by upregulating AMPK/SIRT1/PGC-1α signaling cascade. In conclusion, these findings suggest that DON, QUE, and their combination possess potent protective effects against VPA-induced testicular toxicity.

Nano-quercetin mitigates triazophos-induced testicular toxicity in rats by suppressing oxidative stress and apoptosis

The present study was designed to evaluate the testicular toxicity of triazophos in rats and to check the ameliorative effect of nano-quercetin against triazophos-induced toxicity. Nano-quercetin was synthesized from quercetin and characterized. Male Wistar rats were divided into seven groups. The control group received olive oil as a vehicle orally. The high-dose triazophos group and the low-dose triazophos group received 1/10th LD50 of triazophos (7.6 mg/kg) and 1/20th LD50 of triazophos (3.8 mg/kg), respectively. Two groups of animals were dosed with quercetin and nano-quercetin, both at 50 mg/kg body weight orally. The final two groups received high-dose triazophos with co-administration of quercetin and nano-quercetin, respectively. Triazophos disrupted the male endocrine axis by reducing the levels of steroidogenic enzymes 3-β-HSD and 17-β-HSD in testicular cells, further reducing FSH and testosterone. Also, triazophos increased the reactive oxygen species, induced lipid peroxidation, decreased the mitochondrial membrane potential, and elevated the number of apoptotic cells in rat testes. Nano-quercetin ameliorated the testicular oxidative stress and apoptotic and endocrine parameters more efficiently than quercetin. Besides, nano-quercetin alleviated the histopathological and biochemical alterations of triazophos. It is concluded that nano-quercetin has higher anti-oxidant efficacy than quercetin in protecting rats against triazophos-induced testicular toxicity.

Does resveratrol reduce cisplatin-induced ovarian damage?

OBJECTIVE

The objective of this study was to investigate the protectiveness of resveratrol on cisplatin-induced damage to the ovary using experimental models.

METHODS

A total of 30 female Wistar-Albino rats constituted the research material. The rats were categorized into three groups: Group 1 was administered one milliliter of 0.9% NaCl solution, Group 2 was administered 7.5 mg/kg cisplatin, and Group 3 was administered 7.5 mg/kg cisplatin and 10 mg/kg resveratrol. Ovaries were extirpated in all groups and subjected to biochemical and histopathological tests. Cisplatin-induced damage to ovarian tissue was graded and scored as the total histopathological findings score. The ovarian function was assessed using immunohistochemical staining for c-kit expression. Rats' malondialdehyde, catalase, and superoxide dismutase levels were determined.

RESULTS

The histopathological finding score was significantly higher in Group 2 than in other groups (p<0.05). The superoxide dismutase and catalase levels were significantly higher in Group 3 than in Group 2 (p<0.001 for both cases). The malondialdehyde level was significantly higher in Group 2 than in Group 3 (p<0.001).

CONCLUSION

The study findings demonstrated that resveratrol reduced ovarian injury and enhanced biochemical parameters following cisplatin-induced ovary damage in experimental models.

Selective Adsorption of Quercetin by the Sol-Gel Surface Molecularly Imprinted Polymer

Quercetin, as one of the most biologically active natural flavonoids, is widely found in various vegetables, fruits and Chinese herbs. In this work, molecularly imprinted polymer (MIP) was synthesized through surface molecular imprinting technology with sol-gel polymerization mechanism on SiO₂ at room temperature using quercetin as the template, SiO₂ as the supporter, 3-aminopropyltriethoxysilane (APTES) as the functional monomer, and tetraethoxysilane (TEOS) as the cross-linker. The prepared MIP was characterized via scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR) and nitrogen adsorption measurements to validate its surface morphology, structure and functionality. SEM images revealed that the morphology of MIP was rough and spherical with the particle size of 260 nm larger than that of the support SiO₂. In the FTIR spectra of MIP, the band around 1499 cm^-1 and 2932 cm^-1 were assigned to N-H and C-H groups, respectively. The results indicated that the imprinted polymer layers were grafted on the surface of SiO₂ and the MIP had been successfully prepared. Since the specific surface area and pore volume of MIP were markedly higher than those of NIP and SiO₂ and were 52.10 m² g^-1 and 0.150 cm³ g^-1, respectively, it was evident that the imprinting process created corresponding imprinted cavities and porosity. The MIP for adsorbing quercetin was evaluated by static adsorption experiment. The results indicated that the adsorption equilibrium could be reached within 90 min and the maximum adsorption capacity was as high as 35.70 mg/g. The mechanism for adsorption kinetics and isotherm of MIP for quercetin was proved to conform the pseudo-second-order kinetics model (R² = 0.9930) and the Freundlich isotherm model (R² = 0.9999), respectively, revealing that chemical adsorption and heterogeneous surface with multilayer adsorption dominated. In contrast to non-imprinted polymer (NIP), the MIP demonstrated high selectivity and specific recognition towards quercetin whose selectivity coefficients for quercetin relative to biochanin A were 1.61. Furthermore, the adsorption capacity of MIP can be maintaining above 90% after five regeneration cycles, indicating brilliant reusability and potential application for selective adsorption of quercetin.

Ameliorative effect of gallic acid on cisplatin-induced ovarian toxicity in rats

The aim of the present study was to evaluate the protective effect of gallic acid (GA) against cisplatin (CDDP)-induced ovarian toxicity, for the first time. The ovarian damage was generated with CDDP (5 mg/kg) intraperitoneally (i.p.) administration in rats. GA (2.5 and 5 mg/kg) were administered i.p. for 3 consecutive days. The study was carried out in 5 main groups containing 6 rats in each group: control, GA (5 mg/kg), CDDP, CDDP + GA (2.5 mg/kg) and CDDP + GA (5 mg/kg). The levels of ovarian malondialdehyde (MDA), total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), catalase (CAT), 8-hydroxy-2'-deoxyguanosine (8-OHdG), caspase-3 and tumor necrosis factor-alpha (TNF-α) were determined. Hematoxylin and eosin staining method was employed for the histopathological examination. In the CDDP group, it is determined that statistically significant decreasing in the levels of TAS and CAT, and increasing in the levels of MDA, TOS, OSI, 8-OHdG, caspase-3 and TNF-α (p < 0.05) compared with control group. GA administrations statistically significantly restored this damage (p < 0.05). Although vascular congestion, edema, hemorrhage, follicular degeneration and leukocyte infiltration were significantly higher in the CDDP group than in the control group, GA administrations statistically significantly restored these damages (p < 0.05). In conclusion, this study showed that GA prevented CDDP-induced ovarian damage with its antioxidant, anti-apoptotic and anti-inflammatory activities. More comprehensive studies are needed to see the underlying mechanisms.

Melatonin Mitigates Cisplatin-Induced Ovarian Dysfunction via Altering Steroidogenesis, Inflammation, Apoptosis, Oxidative Stress, and PTEN/PI3K/Akt/mTOR/AMPK Signaling Pathway in Female Rats

Ovarian damage and fertility impairment are major side effects of chemotherapy in pre-menopausal cancer patients. Cisplatin is a widely used chemotherapeutic drug. The present study was designed to assess the ameliorative effects of melatonin as an adjuvant for fertility preservation. Thirty-two adult female Wistar rats were divided randomly into four equal groups: Control, Melatonin, Cisplatin (CP) treated, and CP + Melatonin treated. The cisplatin-treated group showed decreased body and ovarian weights, decreased serum E2 and AMH, increased serum LH and FSH, reduced ovarian levels of SOD, CAT, GSH, and TAC, and increased ovarian MDA. The histopathological examination of the cisplatin-treated group showed deleterious changes within ovarian tissue in the form of damaged follicles and corpus luteum, hemorrhage, and inflammatory infiltrates with faint PAS reaction in zona pellucida, increased ovarian collagen deposition, and marked expression of caspase-3 immune reaction in granulosa and theca cells, stroma, and oocytes. Alongside, there was a significant downregulation in the mRNA expression of steroidogenic enzymes, IL10, AMPK, PI3K, AKT, mTOR, and PTEN, while TGF-β1, IL1β, IL6, TNF-α, NF-Kβ, P53, p38-MAPK, JNK, and FOXO3 mRNA expressions were upregulated in cisplatin-treated rats' ovarian tissue. Coadministration of cisplatin-treated rats with melatonin reversed these changes significantly. In conclusion, melatonin's antioxidant, anti-inflammatory, and anti-apoptotic activities could modulate ovarian disturbances induced by cisplatin and preserve fertility.

Protective Effects of Antioxidants on Cyclophosphamide-Induced Ovarian Toxicity

The most common limitation of anticancer chemotherapy is the injury to normal cells. Cyclophosphamide, which is one of the most widely used alkylating agents, can cause premature ovarian insufficiency and infertility since the ovarian follicles are extremely sensitive to their effects. Although little information is available about the pathogenic mechanism of cyclophosphamide-induced ovarian damage, its toxicity is attributed to oxidative stress, inflammation, and apoptosis. The use of compounds with antioxidant and cytoprotective properties to protect ovarian function from deleterious effects during chemotherapy would be a significant advantage. Thus, this article reviews the mechanism by which cyclophosphamide exerts its toxic effects on the different cellular components of the ovary, and describes 24 cytoprotective compounds used to ameliorate cyclophosphamide-induced ovarian injury and their possible mechanisms of action. Understanding these mechanisms is essential for the development of efficient and targeted pharmacological complementary therapies that could protect and prolong female fertility.

p-Coumaric acid alleviates cisplatin-induced ovarian toxicity in rats

OBJECTIVE

The therapeutic value of cisplatin (CDDP) as an anticancer drug is limited by its ovo-otoxicity. The effect of natural phenolic acids in the prevention of many diseases related to oxidative stress has been reported. Here, the ability of p-coumaric (pCA) acid, a member of phenolic acids, to protect rat ovary tissue against CDDP-induced oxidative stress was investigated.

METHODS

The study was carried out in five main groups containing six rats in each group: control, pCA (4 mg/kg), CDDP, CDDP plus pCA (2 mg/kg), and CDDP plus pCA (4 mg/kg). The levels of ovarian malondialdehyde (MDA), total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), catalase (CAT), 8-hydroxy-2'-deoxyguanosine (8-OHdG), caspase-3, and tumor necrosis factor-alpha (TNF-α) were determined. Hematoxylin and eosin staining method was employed for the histopathological examination.

RESULTS

In the CDDP group, it is determined that statistically significant decreasing in the levels of TAS and CAT, and increasing in the levels of MDA, TOS, OSI, 8-OHdG, caspase-3, and TNF-α compared with control group (p < 0.05). pCA administration statistically significantly restored this damage in a dose-dependent manner (p < 0.05). Although vascular congestion, edema, hemorrhage, follicular degeneration, and leukocyte infiltration were significantly higher in the CDDP group than in the control group, pCA administrations statistically significantly restored these damages (p < 0.05).

CONCLUSIONS

The data presented here indicate that pCA protects ovarian tissues of rats against CDDP-induced oxidative stress, inflammation, and apoptosis. It may be worthy to consider the usefulness of pCA as adjuvant therapy in cancer management.