A histopathological and stereological study of liver damage in female rats caused by mercury vapor

Promising the potential of β-caryophyllene on mercury chloride-induced alteration in cerebellum and spinal cord of young Wistar albino rats

Mercury chloride (ME) is a chemical pollutant commonly found in the environment, which can contribute to undesirable health consequence worldwide. The current study investigated the detrimental impact of ME on the cerebellum and spinal cord tissues in 6-8-week-old female rats. We also evaluated the neuroprotective efficacy of β-caryophyllene (BC) against spinal and cerebellar changes caused by ME. Thirty-five young Wistar albino rats were randomly chosen and assigned into five groups: control (CO), olive oil (OI), ME, BC, ME + BC. All samples were analysed by means of unbiased stereological, biochemical, immunohistochemical, and histopathological methods. Our biochemical findings showed that SOD level was significantly increased in the ME group compared to the CO group (p < 0.05). We additionally detected a statistically significant decrease in the number of cerebellar Purkinje cells and granular cells, as well as spinal motor neuron in the ME group compared to the CO group (p < 0.05). In the ME + BC group, the number of Purkinje cells, granular cells, and spinal motor neurons was significantly higher compared to the ME group (p < 0.05). Decreased SOD activity in the ME + BC group was also detected than the ME group (p < 0.05). Immunohistochemical (the tumour necrosis factor-alpha (TNF-α)) and histopathological examinations also exhibited crucial information in each of the group. Taken together, ME exposure was associated with neurotoxicity in the cerebellum and spinal cord tissues. BC treatment also mitigated ME-induced neurological alteration, which may imply its potential therapeutic benefits.

Current status of advancement in remediation technologies for the toxic metal mercury in the environment: A critical review

Currently, pollution due to heavy metals, in particular dissolved mercury, is a major concern for society and the environment. This work aims to evaluate the current scenario regarding the removal/elimination of mercury. Mercury removal through adsorption is mainly done through artificial resins and metallic-organic frameworks. In the case of the zinc organic framework, it was able to adsorb Hg2+, reaching an adsorption capacity of 802 mg g-1. As for the Hg(0) the coconut husk was found to have the lowest equilibrium time, 30 min, and the highest adsorption capacity of 956.2 mg g-1. Experimental reports and molecular simulation indicate that the adsorption of mercury and other chemical forms occurs due to electrostatic interactions, ion exchange, precipitation, complexation, chelation, and covalent bonds, according to the material nature. The reported thermodynamic results show that, in most cases, the mercury adsorption has an endothermic nature with enthalpy levels below 40 kJ mol-1. Thermal and chemical regeneration methods lead to a similar number of 5 cycles for different materials. The presence of other ions, in particular cadmium, lead, and copper, generates an antagonistic effect for mercury adsorption. Regarding the other current technologies, it was found that mercury removal is feasible through precipitation, phytoremediation, and marine microalgae; all these methods require constant chemicals or a slow rate of removal according to the conditions. Advanced oxidative processes have noteworthy removal of Hg(0); however, Fenton processes lead to mineralization, which leads to Fe2+ and Fe3+ in solution; sonochemical processes are impossible to scale up at the current technology level; and electrochemical processes consume more energy and require constant changes of the anode and cathode. Overall, it is possible to conclude that the adsorption process remains a more friendly, economical, and greener process in comparison with other processes.

Biochemical, morphological and molecular assessments of n butanol fraction of Phoenix dactylifera L. following exposure to inorganic mercury on the liver of Wistar rats

BACKGROUND

Mercury chloride (HgCl2) damages tissues it comes in contact with in sufficient concentration. This study evaluated the protective effects of n-butanol fraction of Phoenix dactylifera (BFPD) on mercury-triggered liver toxicity in Wistar rats. 25 male rats were divided into 5 groups of 5 rats each. Group I was administered 2 ml/kg of distilled water; group II was administered 5 mg/kg of HgCl2; group III was administered 500 mg/kg of BFPD + 5 mg/kg of HgCl2; group IV was administered 1000 mg/kg of BFPD + 5 mg/kg of HgCl2, while group V was administered 100 mg/kg of silymarin + 5 mg/kg of HgCl2. orally for 2 weeks. The rats were euthanized and liver tissue blood samples were collected for histological, histochemical, stereological, immunohistochemical, molecular, and biochemical studies.

RESULTS

The results revealed that HgCl2 induced oxidative stress in the rats evident by histoarchitectural distortions and altered levels of liver enzymes, proteins, and oxidative stress biomarkers when compared to the control. However, BFPD treatment restored these changes. Glutathione peroxidase levels decreased (p < 0.05) in the HgCl2-treated group when compared to the control and BFPD-treated groups. HgCl2 group revealed reduced reactivity with histochemical and immunohistochemical stains (Masson's Trichrome and B cell Lymphoma 2) when compared to the control, with a significant decrease in quantified liver Bcl-2 stain intensity when compared to the silymarin-treated group. BFPD administration revealed normal staining intensity comparable to the control. HgCl2 administration revealed a remarked decrease in the number of hepatocytes when compared to the control, BFPD, and silymarin groups. BFPD preserved (p < 0.05) the stereological features when compared to the HgCl2-treated group. GPx activity in the liver decreased (p < 0.05) with HgCl2 administration when compared to the control and silymarin-treated groups. BFPD attenuated GPx gene activity to levels similar to the control indicating some level of amelioration against HgCl2-induced toxicity.

CONCLUSIONS

The ability of BFPD to mitigate HgCl2 triggered liver alterations could be attributed to the antioxidant property of its flavonoid content. Therefore, BFPD may be a potential candidate for treating and managing liver-induced mercury intoxication.

Neuroprotective potential of Ginkgo biloba on alteration of rat cerebellum following prenatal exposure to cyclophosphamide

The cytotoxicity of chemotherapeutic drugs is known due to its non-selective effect not only on cancer cells but also on healthy cells. This study investigated the cerebellar alteration in rats prenatally exposed to cyclophosphamide (SK, 20 mg/kg). We also evaluated the neuroprotective potential of Ginkgo biloba (GB, 80 mg/kg/day) against possible biological changes caused by SK in the cerebellar tissues. Twenty adult female rats (weighing 230-280 g, 12 weeks old) were divided into five groups: control, sham, SK, GB, and SK + GB. After mating, pregnant rats was treated with SK in the SK and SK + GB groups and GB in the GB and SK + GB groups from day 13 to day 21 of gestation. After parturition, eight female rats were randomly selected from each group. On day 32 after birth, the cerebellar tissues were dissected and then examined under light microscope using stereological and histopathological methods. Stereological findings showed that the total number of Purkinje cells and granular cells were significantly decreased in the SK group than the control group (p < 0.05). In addition, the mean volumes of molecular layer, granular layer, white matter, and cerebellum were significantly decreased in the SK group compared to the control group (p < 0.05). In the SK + GB group, the total number Purkinje cell, and granular cells, as well as the mean volumes of molecular layer, granular layer, white matter, and cerebellum were significantly increased than the SK group (p < 0.05). Histopathological evaluation also confirmed our stereological findings in the cerebellar tissues. Our results showed that prenatal exposure to SK caused significant changes in the cerebellar architectures of rats, and that GB administration significantly attenuated the deleterious effect of SK on the cerebellar tissues.

Integration of proteomics and network toxicology reveals the mechanism of mercury chloride induced hepatotoxicity, in mice and HepG2 cells

Mercury is one heavy metal toxin that could cause severe health impairments. Mercury exposure has become a global environmental issue. Mercury chloride (HgCl₂) is one of mercury's main chemical forms, but it lacks detailed hepatotoxicity data. The present study aimed to investigate the mechanism of hepatotoxicity induced by HgCl₂ through proteomics and network toxicology at the animal and cellular levels. HgCl₂ showed apparent hepatotoxicity after being administrated with C57BL/6 mice (16 mg/kg.bw, oral once a day, 28 days) and HepG2 cells (100 μmol/L, 12 h). Otherwise, oxidative stress, mitochondrial dysfunction and inflammatory infiltration play an important role in HgCl₂-induced hepatotoxicity. The differentially expressed proteins (DEPs) after HgCl₂ treatment and enriched pathways were obtained through proteomics and network toxicology. Western blot and RT-qPCR results showed Acyl-CoA thioesterase 1 (ACOT1), Acyl-CoA synthetase short chain family member 3 (ACSS3), Epidermal growth factor receptor (EGFR), Apolipoprotein B (APOB), Signal transducer and activator of transcription 3 (STAT3), Alanine--glyoxylate aminotransferase (AGXT), cytochrome P450 3A5(CYP3A5), CYP2E1 and CYP1A2 may be the major biomarkers for HgCl₂-induced hepatotoxicity, which involved chemical carcinogenesis, fatty acid metabolism, CYPs-mediated metabolism, GSH metabolism and others. Therefore, this study can provide scientific evidence for the biomarkers and mechanism of HgCl₂-induced hepatotoxicity.

Investigation of Changes in Liver Microanatomy in the Steatosis Model Created by Permanent Canula in Rats

Objective: The knowledge of nonalcoholic fatty liver disease (NAFLD) and Nonalcoholic Steatohepatitis (NASH) is limited to the findings from available suitable models for this disease. A number of rodent models have been described in which relevant liver pathology develops in an appropriate metabolic context. In this experimental study, it was aimed to create a new liver fat model by giving fat from the portal vein of rats and to visualize the changes in the liver with advanced microscopic techniques. Methods: 28 female rats were used in the study. Permanent intraabdominal cannulas were inserted into the portal vein of the rats. Rats were randomly divided four group. Intralipid 20% substance was injected through cannula to the experimental groups during the test period. Control group received saline at the same rate. At the end of the experiment, the animals were visualized with a laser speckle microscope and livers were divided into sections according to the stereological method. The sections were painted with Hematoxylin-Eosin, Oil red o, Masson trichoma, Bodipy, Nile red. Sections were evaluated under a microscope. Results: Ballooning, inflammation and fibrosis were observed in the 2 week intralipid group. In the 1 week intralipid group, the rate of parenchyma decreased while the sinusoid rate increased, and sinusoid rate increased significantly in the 2 week intralipid (p˂0.05). Conclusion: According to the findings, steatohepatitis was detected in the 2 week intralipid, whereas only steatosis was observed in the 1 week intralipid. Thus, it was concluded that the newly formed rat model causes steatosis.

Stereological and Histological Assessment of the Umbilical Cord in New-Born Rat

Background

Umbilical cord plays a crucial role in the continuation of pregnancy by transferring nutrition and oxygen across the placenta to the fetus. We aimed to investigate the morphometrical and histological features of the umbilical cords in new-born rats.

Materials and Methods

The adult male and female rats were chosen for matting purpose in the present study. Briefly, ten adult Wistar albino rats (female, n = 5; male, n = 5) were randomly assigned into five groups of two animals (female, n = 1; male, n = 1). Immediately after parturition, two umbilical cords of new-born rats (0-day-old) from each group were randomly selected. Finally, ten umbilical cord samples were examined using the histological and stereological methods in the light and electron microscopes.

Results

The total numbers of Hofbauer cells and mesenchymal stromal cells was estimated statistically. We also calculated the mean volume of umbilical cords, arteries and veins, as well as arterial and venous lumens. Our histological findings also exhibited the histological features of Hofbauer cells, mesenchymal stromal cell cells, and blood vessels.

Conclusion

Our findings showed more detailed information about umbilical cord tissues and their components, and that may contribute to the diagnose of umbilical cord complications in the developing fetus.

Molecular mechanism of heavy metals (Lead, Chromium, Arsenic, Mercury, Nickel and Cadmium) - induced hepatotoxicity - A review

Heavy metals pose a serious threat if they go beyond permissible limits in our bodies. Much heavy metal's viz. Lead, Chromium, Arsenic, Mercury, Nickel, and Cadmium pose a serious threat when they go beyond permissible limits and cause hepatotoxicity. They cause the generation of ROS which in turn causes numerous injuries and undesirable changes in the liver. Epidemiological studies have shown an increase in the levels of such heavy metals in the environment posing a serious threat to human health. Epigenetic alterations have been seen in the event of exposure to such heavy metals. Apoptosis, caspase activation as well as ultrastructural changes in the hepatocytes have also been seen due to heavy metals. Inflammation involving TNF-alpha, pro-inflammatory cytokines, MAPK, ERK pathways have been seen in the event of heavy metal hepatotoxicity. All these have shown that these heavy metals pose a serious threat to human health in particular and the environment as a whole.

Neuroprotective efficacy of luteolin on a 900-MHz electromagnetic field-induced cerebellar alteration in adult male rat

The adverse health consequences of exposure to electromagnetic field emitted from cell phone has recently raised public concerns worldwide. Also, the Global System for Mobile Communications (GSM) standard that operates in 900 MHz frequency is the most popular. Therefore, we aimed to investigate the adverse effect of exposure to 900 MHz EMF (1 h/day) on the cerebella of 12-week-old rats. We also evaluated the protective activity of luteolin (20 μg/kg/day) against possible biological change in the cerebellar tissues exposed to EMF. Twenty-four male wistar albino rats were randomly assigned into four group of six rats: Control, EMF, EMF + luteolin, luteolin. Serological and biochemical analyses, as well as histopathological examination were performed on all cerebellar samples. We found that SOD (superoxide dismutase) level was significantly increased in the EMF group compared to the control group (p < 0.05). To the contrary, decreased SOD activity was detected in the EMF + luteolin group compared to control group (p < 0.05). The total number of Purkinje and granular cells was significantly decreased in the EMF group compared to the control group (p < 0.05). In the EMF + luteolin group, the total number of Purkinje and granular cells was significantly higher than the EMF group (p < 0.05). Histopathological evaluation also showed destructive damage to the architectures of cerebellar tissues. Our results suggest that exposure to EMF may cause cellular damage to the rat cerebellum. Further, the improvement of cerebellar damage may have resulted from antioxidant efficacy of luteolin by alleviating oxidative stress.

A stereological study of the effects of mercury inhalation on the cerebellum

Mercury in the environment that arises from organic and inorganic sources can cause irreversible damage to the nervous system. Toxicity may be direct or may arise from interactions with other metals in the environment. We evaluated the possible effects of mercury vapor on rat cerebellum. Twelve adult female rats were divided into control and experimental groups. The rats in the experimental group were exposed to mercury vapor for 9 h/day for 45 days. Cerebellar tissue samples were evaluated using stereology and for histopathology. The total number of Purkinje cells was estimated using a physical disector method. We found that in the experimental group, overall volume decreased and the number of Purkinje cells was reduced. We also found cellular damage including pycnotic nuclei, eosinophilic cytoplasm and vacuolization; these features were absent in the control group. We found that chronic exposure to inorganic mercury vapor is toxic to the cerebellum.