The protective role of melatonin in cadmium-induced proliferation of ovarian cancer cells

An insight on the plausible biological and non-biological detoxification of heavy metals in tannery waste: A comprehensive review

A key challenge for the tannery industries is the volume of tannery waste water (TWW) generated during the processing of leather, releasing various forms of toxic heavy metals resulting in uncontrolled discharge of tannery waste (TW) into the environment leading to pollution. The pollutants in TW includes heavy metals such as chromium (Cr), cadmium (Cd), lead (Pb) etc, when discharged above the permissible limit causes ill effects on humans. Therefore, several researchers have reported the application of biological and non-biological methods for the removal of pollutants in TW. This review provides insights on the global scenario of tannery industries and the harmful effects of heavy metal generated by tannery industry on micro and macroorganisms of the various ecological niches. It also provides information on the process, advantages and disadvantages of non-biological methods such as electrochemical oxidation, advanced oxidation processes, photon assisted catalytic remediation, adsorption and membrane technology. The various biological methods emphasised includes strategies such as constructed wetland, vermitechnology, phytoremediation, bioaugmentation, quorum sensing and biofilm in the remediation of heavy metals from tannery wastewater (TWW) with special emphasize on chromium.

Melatonin counteracts cadmium-induced rat testicular toxicity via the mechanistic target rapamycin (mTOR) pathway

The protective action of melatonin (MLT) against the harmful effects of cadmium (Cd) on testicular activity in rats has been documented previously; however, the involved molecular mechanisms have yet to be elucidated. Herein, we investigate the involvement of the mammalian target of rapamycin (mTOR) on the ability of MLT to counteract the damage induced by Cd on the rat testicular activity. Our study confirmed that Cd has harmful effects on the testes of rats and the protective action exerted by MLT. We reported, for the first time, that the addition of rapamycin (Rapa), a specific mTOR inhibitor, to animals co-treated with Cd and MLT completely abolished the beneficial effects exerted by MLT, indicating that the mTOR pathway partially modulates its helpful effects on Cd testicular toxicity. Interestingly, Rapa-alone treatment, provoking mTOR inhibition, produced altered morphological parameters, increased autophagy of germ and somatic cells, and reduced serum testosterone concentration. In addition, mTOR inhibition also reduced protein levels of markers of steroidogenesis (3β-Hydroxysteroid dehydrogenase) and blood-testis barrier integrity (occludin and connexin 43). Finally, Rapa altered sperm parameters as well as the ability of mature spermatozoa to perform a proper acrosome reaction. Although further investigation is needed to better clarify the molecular pathway involved in MLT action, we confirm that MLT alleviating Cd effects can be used as a supplement to enhance testicular function and improve male gamete quality.

An overview of the ameliorative efficacy of Catharanthus roseus extract against Cd2+ toxicity: implications for human health and remediation strategies

Rapid industrialization has led to an increase in cadmium pollution, a dangerously toxic heavy metal. Cadmium (Cd) is released into the environment through industrial processes and can contaminate air, water, and soil. This pollution poses a significant risk to human health and has become a pressing concern in many industrialized areas. Due to its extended half-life, it leads to a range of health problems, including hepato-nephritic toxicity, brain damage, and degenerative bone disorders. Intoxication alters various intracellular parameters, leading to inflammation, tissue injury, and oxidative stress within cells, which disrupts normal cellular functions and can eventually result in cell death. It has also been linked to the development of bone diseases such as osteoporosis. These adverse effects highlight the urgent need to address cadmium pollution and find effective solutions to mitigate its impact on human health. This article highlights the Cd-induced risks and the role of Catharanthus roseus (C. roseus) extract as a source of alternative medicine in alleviating the symptoms. Numerous herbal remedies often contain certain bioactive substances, such as polyphenols and alkaloids, which have the power to mitigate these adverse effects by acting as antioxidants and lowering oxidative cell damage. Research conducted in the field of alternative medicine has revealed its enormous potential to meet demands that may be effectively used in safeguarding humans and their environment. The point of this review is to investigate whether C. roseus extract, known for its bioactive substances, is being investigated for its potential to mitigate the harmful effects of cadmium on health. Further investigation is needed to fully understand its effectiveness. Moreover, it is important to explore the potential environmental benefits of using C. roseus extract to reduce the negative effects of Cd. This review conducted in the field of alternative medicine has revealed its enormous potential to meet demands that could have significant implications for both human health and environmental sustainability.

Sex-dependent vascular effects of cadmium sub-chronic exposure on rats

Cadmium exposure is related to several cardiovascular diseases, such as hypertension, atherosclerosis and endothelial dysfunction. However, the toxic effect of cadmium can be dependent on the sex when examined sex in experimental models. The aim of this study was to analyze the effects of cadmium exposure on the cardiovascular system of male and female rodents. The experiments were carried out on both-sexes Wistar at 4 months of age, where from 3 months onwards, cadmium (CdCl2 100 mg/l in placed the drinking water for 30 days) or vehicle delivered (distilled water) was ingested. Before and after 30 days of exposure to cadmium, systolic blood pressure was regularly measured. After exposure, blood was collected to measure dosage of cadmium, in male and female, and estrogen in females. Vascular reactivity to phenylephrine (Phe), acetylcholine (ACh), and sodium nitroprusside (SNP) was studied at respective isolated aortic segments. After the period to Cd-exposure, systolic blood pressure was increased only in the male rats. Males also had higher levels of plasma cadmium than those of female rats, and exposure to the metal did not affect the amount of estrogen produced in the female rats. Increased myeloperoxidase (MPO) activity was also observed in both the males and females that had been exposed to the metal. Moreover, exposure to the cadmium reduced the ACh relaxation and increased vascular reactivity to Phe, resulting in an imbalance between nitric oxide superoxide anion in the isolated aorta of male rats. In female rats, sub-chronic cadmium exposure did not modify the vascular reactivity to Phe and neither to the ACh. The present study revealed that the Cd exposure for 30 days induced sex-dependent cardiovascular abnormalities.

Antioxidant and genoprotective effects of osthole against cadmium-induced DNA damage: an in vitro study using comet assay

Background and purpose

Osthole, a plant-derived coumarin, has shown numerous pharmacological effects. However, its genoprotective effects against cadmium-induced DNA damage have not been determined yet. Therefore, this project aimed to assess the effectiveness of osthole against genotoxicity caused by cadmium.

Experimental approach

For this purpose, human umbilical vein endothelial cells (HUVECs) were incubated with various concentrations of osthole (40, 60, 80, and 120 µM) 24 h before cadmium chloride (CdCl₂) treatment (40 µM), and then DNA damage was evaluated by comet assay. Furthermore, DPPH and free thiol group assays were applied to evaluate reactive oxygen species scavenger and antioxidant capacities of osthole.

Findings / Results

In the present study, all concentrations of osthole significantly decreased CdCl₂-induced DNA damage. Furthermore, the antioxidant properties of the osthole were confirmed by DPPH and free thiol assays.

Conclusion and implications

Overall, the findings of this project revealed that osthole could ameliorate cadmium-induced genotoxicity probably by its antioxidant activity.

The environment and female reproduction: Potential mechanism of cadmium poisoning to the growth and development of ovarian follicle

Cadmium (Cd) is ubiquitous in our environment and can easily bioaccumulate into the organism after passage through the respiratory and digestive tracts. Long-term exposure to Cd can result in the significant bioaccumulation in organism because of its long biological high-life (10-30 years), which exerts irreversible damages on the health of animals and humans. Although there are increased evidence of impeding the normal function of female reproduction resulted from Cd exposure, the mechanism of the negative action of Cd on the growth and development of ovarian follicle remains enigmatic. Thus, the purpose of the presented study is to summarize available literature which describing Cd-related toxicity involved in the adverse effects on the growth and development of the ovarian follicle. In conclusion, it is suggested that Cd causes damage to the folliculogenesis of mammalians, which results in the decline in the number and quality of ovulated oocytes and the failure in the fertilization. The mechanism behinds that may be linked to the interference to the production of reproductive hormones and the augment of reactive oxygen species (ROS). Furthermore, the enhanced ROS, in turn, impairs various molecules including proteins, lipids and DNA, as well as the balance of the antioxidant defense system, mitochondrial homeostasis, endoplasmic reticulum, autophagy and epigenetic modification. This review is expected to elaborate the toxic mechanism of Cd exposure to the growth and development of ovarian follicles and provide essential remediation strategies to alleviate the damage of Cd to female reproductive health.

Curative Potential of Substances with Bioactive Properties to Alleviate Cd Toxicity: A Review

Rapid urbanization and industrialization have led to alarming cadmium (Cd) pollution. Cd is a toxic heavy metal without any known physiological function in the organism, leading to severe health threat to the population. Cd has a long half-life (10-30 years) and thus it represents serious concern as it to a great extent accumulates in organs or organelles where it often causes irreversible damage. Moreover, Cd contamination might further lead to certain carcinogenic and non-carcinogenic health risks. Therefore, its negative effect on population health has to be minimalized. As Cd is able to enter the body through the air, water, soil, and food chain one possible way to defend and eliminate Cd toxicities is via dietary supplements that aim to eliminate the adverse effects of Cd to the organism. Naturally occurring bioactive compounds in food or medicinal plants with beneficial, mostly antioxidant, anti-inflammatory, anti-aging, or anti-tumorigenesis impact on the organism, have been described to mitigate the negative effect of various contaminants and pollutants, including Cd. This study summarizes the curative effect of recently studied bioactive substances and mineral elements capable to alleviate the negative impact of Cd on various model systems, supposing that not only the Cd-derived health threat can be reduced, but also prevention and control of Cd toxicity and elimination of Cd contamination can be achieved in the future.

Melatonin in Cancer Treatment: Current Knowledge and Future Opportunities

Melatonin is a pleotropic molecule with numerous biological activities. Epidemiological and experimental studies have documented that melatonin could inhibit different types of cancer in vitro and in vivo. Results showed the involvement of melatonin in different anticancer mechanisms including apoptosis induction, cell proliferation inhibition, reduction in tumor growth and metastases, reduction in the side effects associated with chemotherapy and radiotherapy, decreasing drug resistance in cancer therapy, and augmentation of the therapeutic effects of conventional anticancer therapies. Clinical trials revealed that melatonin is an effective adjuvant drug to all conventional therapies. This review summarized melatonin biosynthesis, availability from natural sources, metabolism, bioavailability, anticancer mechanisms of melatonin, its use in clinical trials, and pharmaceutical formulation. Studies discussed in this review will provide a solid foundation for researchers and physicians to design and develop new therapies to treat and prevent cancer using melatonin.

Melatonin: A Potential Therapeutic Option for Breast Cancer

Melatonin has significant inhibitory effects in numerous cancers, especially breast cancer. In estrogen receptor (ER)-positive human breast cancer, the oncostatic actions of melatonin are mainly achieved by suppressing ER mRNA expression and ER transcriptional activity via the MT1 receptor. Melatonin also regulates the transactivation of nuclear receptors, estrogen-metabolizing enzymes, and the expression of related genes. Furthermore, melatonin suppresses tumor aerobic glycolysis, critical cell-signaling pathways relevant to cell proliferation, survival, metastasis, and overcomes drug resistance. Studies in animal and human models indicate that disruption of the circadian nocturnal melatonin signal promotes the growth, metabolism, and signaling of human breast cancer, resulting in resistance to hormone therapy and chemotherapy, which may be reversed by melatonin.

Effects of melatonin on uterine hypertrophy/hyperplasia: A preliminary experimental rat study

Endometrial hyperplasia is a process of endometrial proliferation that results in a thickening of the endometrial tissue. Melatonin might be able to change the pathophysiological process and prognosis into a positive way that might prevent and heal endometrial hyperplasia, which is the first stage of endometrial cancer. For this perspective, we tried to investigate the effect of melatonin on uterine hypertrophy/hyperplasia in an experimental rat model. Forty Wistar-Albino rats were undergone bilateral oophorectomy and randomized into four groups. To create a model of uterine hypertrophy/hyperplasia in all groups, except the control group [C] (n = 10), 4 mg/kg/day estradiol hemihydrate were given for 14 days. The uterine hypertrophy/hyperplasia was evaluated histopathologically in the left uterine horns, then the groups were treated for 14 days as follows; melatonin (10 mg/kg/day/po) [M] (n = 10), melatonin + estradiol hemihydrate (10 mg/kg/day/po and 4 mg/kg/day/po) [M + E] (n = 10), and dark environment [D] (n = 10). Finally, the effects of the melatonin were examined histopathologically in the right uterine horns. An uterine hypertrophy/hyperplasia model was established in all groups compared to the control group (p < 0.05). In the [M] and [M + E] groups, epithelial cell height and luminal epithelial cell height significantly decreased (41μm vs 12μm, p = 0.005; 14μm vs 10μm, p = 0.005, respectively for [M] group) and (32μm vs 14μm, p = 0.012; 17μm vs 10μm, p = 0.017, respectively for [M + E] group). The [D] group exhibited a significant decrease in epithelial cell height (33μm vs 20μm, p = 0.017). With or without estrogen exposure, melatonin-treated and physiologically melatonin-released rats experienced a significant uterine hypertrophy/hyperplasia recovery. Melatonin may have protective effects on endometrial hyperplasia.

The Role of Natural Antioxidants Against Reactive Oxygen Species Produced by Cadmium Toxicity: A Review

Cadmium (Cd) is a significant ecotoxic heavy metal that adversely affects all biological processes of humans, animals and plants. Exposure to acute and chronic Cd damages many organs in humans and animals (e.g. lung, liver, brain, kidney, and testes). In humans, the Cd concentration at birth is zero, but because the biological half-life is long (about 30 years in humans), the concentration increases with age. The industrial developments of the last century have significantly increased the use of this metal. Especially in developing countries, this consumption is higher. Oxidative stress is the imbalance between antioxidants and oxidants. Cd increases reactive oxygen species (ROS) production and causes oxidative stress. Excess cellular levels of ROS cause damage to proteins, nucleic acids, lipids, membranes and organelles. This damage has been associated with various diseases. These include cancer, hypertension, ischemia/perfusion, cardiovascular diseases, chronic obstructive pulmonary disease, diabetes, insulin resistance, acute respiratory distress syndrome, idiopathic pulmonary fibrosis, asthma, skin diseases, chronic kidney disease, eye diseases, neurodegenerative diseases (amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease, and Huntington disease). Natural antioxidants are popular drugs that are used by the majority of people and have few side effects. Natural antioxidants play an important role in reducing free radicals caused by Cd toxicity. Our goal in this review is to establish the relationship between Cd and oxidative stress and to discuss the role of natural antioxidants in reducing Cd toxicity.

Insights on Melatonin as an Active Pharmacological Molecule in Cancer Prevention: What's New?

Along with playing an important role in circadian rhythm, melatonin is thought to play a significant role in preventing cells from damage, as well as in the inhibition of growth and in triggering apoptosis in malignant cells. Its relationship with circadian rhythms, energetic homeostasis, diet, and metabolism, is fundamental to achieve a better comprehension of how melatonin has been considered a chemopreventive molecule, though very few papers dealing with this issue. In this article, we tried to review the most recent evidence regarding the protective as well as the antitumoral mechanisms of melatonin, as related to diet and metabolic balance. From different studies, it was evident that an intracellular antioxidant defense mechanism is activated by upregulating an antioxidant gene battery in the presence of high-dose melatonin in malignant cells. Like other broad-spectrum antioxidant molecules, melatonin plays a vital role in killing tumor cells, preventing metastasis, and simultaneously keeping normal cells protected from oxidative stress and other types of tissue damage.

Binary-ternary Cd(II)-(hydroxycarboxylic acid)-(aromatic chelator) systems exhibit in vitro cytotoxic selectivity in a tissue-specific manner

Cadmium is a metallotoxin, amply encountered in the environment and derived through physical and anthropogenic activities. Its entry in various organisms leads through water and the food chain to humans, thereby inducing a plethora of pathophysiologies. Delineation of the interactive role of cadmium with physiological and physiologically relevant substrates, requires well-defined forms of cadmium arising from such interactions along with the ensuing chemical reactivity amounting to toxic manifestations and health aberrations. To implement such efforts, low molecular mass substrate metal ion binders are needed, forming species with enhanced solubility and bioavailability. To that end, α-hydroxy isobutyric acid (HIBAH₂) was used in pH-specific synthetic efforts involving bulky aromatic chelators 2,2'-bipyridine (2,2'-bipy) and 1,10-phenanthroline (phen), thus leading to new crystalline materials [Cd(C₄H₇O₃)₂]_n(1), [Cd(C₄H₇O₃)₂(H₂O)₂](2), [{Cd₂(C₄H₇O₃)₂(C₁₀H₈N₂)₂(H₂O)₂}(NO₃)₂]_n·nH₂O(3), and [{Cd₂(C₄H₇O₃)₂(C₁₂H₈N₂)₂(H₂O)₂}(NO₃)₂]_n·2nH₂O(4), which were physicochemically characterized (elemental analysis, FT-IR, NMR, ESI-MS, and X-ray crystallography) in the solid state and solution. Their physicochemical characteristics led to their employment in tissue-specific biological toxicity studies in three different cell lines. Their toxicity profile (cell viability, morphology, chemotacticity) was correlated through genetic biomarkers to apoptotic-necrotic processes, thereby shedding light on cadmium cellular toxicity processes. Finally, the cytoprotective action of specific chelators was examined, lending credence to the notion that appropriately structured chelators and antioxidants may be used as effective deterrent to cadmium toxicity. Collectively, structure-specificity linked to tissue-specific toxicity profiling in well-defined binary-ternary Cd(II)-HIBAH₂ systems exemplifies that metal ion's aberrant interactions in the cellular milieu, meriting further probing into the development of efficient chelators in cadmium detoxification.

Cadmium induces progesterone receptor gene expression via activation of estrogen receptor in human ovarian cancer cells

Cadmium (Cd) as a metalloesterogen may have a role in development of ovarian cancer. One of the critical target genes of estrogens is progesterone receptors (PRs). There are controversial studies on association between Cd, PRs, and cell proliferation. This study investigates the effect of Cd on proliferation of ovarian cancer cell lines, PRA and PRB expression and their relationship. OVCAR3 and SKOV3 cells were treated with CdCl₂ (1-100 nM) and cell proliferation was assayed using bromodeoxyuridine (BrdU) method. The mechanism underlying the proliferative effect of Cd mediated by PRs was examined using cell transfection with PR- small interfering RNA (siRNA) and western blot analysis. Our results showed the involvement of PRs in Cd induced proliferation of ovarian cancer cells. Progesterone receptors are involved in proliferative effect of Cd. Moreover, Cd modified the expression of PRA and PRB and induced ovarian cancer cell proliferation through the change of PRA/PRB ratio. In conclusion, there is a mechanistic association between Cd effects on ovarian cancer cell proliferation, estrogen receptors and PRs expression.

Melatonin May Increase Anticancer Potential of Pleiotropic Drugs

Melatonin (N-acetyl-5-methoxytryptamine) is not only a pineal hormone, but also an ubiquitary molecule present in plants and part of our diet. Numerous preclinical and some clinical reports pointed to its multiple beneficial effects including oncostatic properties, and as such, it has become one of the most aspiring goals in cancer prevention/therapy. A link between cancer and inflammation and/or metabolic disorders has been well established and the therapy of these conditions with so-called pleiotropic drugs, which include non-steroidal anti-inflammatory drugs, statins and peroral antidiabetics, modulates a cancer risk too. Adjuvant therapy with melatonin may improve the oncostatic potential of these drugs. Results from preclinical studies are limited though support this hypothesis, which, however, remains to be verified by further research.