Bromobenzene-induced lethal toxicity in mouse is prevented by pretreatment with zinc sulfate

Gum Arabic nanoformulation rescues neuronal lesions in bromobenzene-challenged rats by its antioxidant, anti-apoptotic and cytoprotective potentials

Bromobenzene (BB) is a hazardous environmental contaminant because of its multiple routes of exposure and the toxicity of its bio-derivates. It could elicit neuronal alterations by stimulating redox imbalance and apoptotic pathways. Gum Arabic (GA) protected the hippocampus of a type 2 diabetic rat model from cognitive decline. Whether gum Arabic nanoemulsion (GANE) can increase the neuroprotectant potency of GA in fighting BB-associated neurological lesions is the question to be answered. To accomplish this objective, 25 adult male Wistar rats were randomly and equally assigned into five groups. Control received olive oil (vehicle of BB). BB group received BB at a dose of 460 mg/kg BW. Blank nanoemulsion (BNE) group supplemented with BNE at 2 mL of 10% w/v aqueous suspension/kg BW. GANE group received GANE at a dose of 2 mL of 10% w/v aqueous suspension/kg BW. BB + GANE group exposed to BB in concomitant with GANE at the same previous doses. All interventions were carried out daily by oral gavage for ten consecutive days. BB caused a marked increase in malondialdehyde and succinate dehydrogenase together with a marked decrease in reduced glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase, and lactate dehydrogenase in the brain. BB was accompanied by pathological deteriorations, amyloidosis, and reduced immuno-expression of integrase interactor 1 in the hippocampal region. Administration of GANE was beneficial in reversing the aforementioned abnormalities. These results pave the road for further discovery of nano-formulated natural products to counter the threats of BB.

Sasa veitchii extract protects against carbon tetrachloride-induced hepatic fibrosis in mice

BACKGROUND

The current study aimed to investigate the hepatoprotective effects of Sasa veitchii extract (SE) on carbon tetrachloride (CCl₄)-induced liver fibrosis in mice.

METHODS

Male C57BL/6J mice were intraperitoneally injected with CCl₄ dissolved in olive oil (1 g/kg) twice per week for 8 weeks. SE (0.1 mL) was administered orally once per day throughout the study, and body weight was measured weekly. Seventy-two hours after the final CCl₄ injection, mice were euthanized and plasma samples were collected. The liver and kidneys were collected and weighed.

RESULTS

CCl₄ administration increased liver weight, decreased body weight, elevated plasma alanine aminotransferase, and aspartate aminotransferase and increased liver oxidative stress (malondialdehyde and glutathione). These increases were attenuated by SE treatment. Overexpression of tumor necrosis factor-α was also reversed following SE treatment. Furthermore, CCl₄-induced increases in α-smooth muscle actin, a marker for hepatic fibrosis, were attenuated in mice treated with SE. Moreover, SE inhibited CCl₄-induced nuclear translocation of hepatic nuclear factor kappa B (NF-κB) p65 and phosphorylation of mitogen-activated protein kinase (MAPK).

CONCLUSION

These results suggested that SE prevented CCl₄-induced hepatic fibrosis by inhibiting the MAPK and NF-κB signaling pathways.

Lethal chronotoxicity induced by seven metal compounds in mice

The aim of the present study is to investigate the "chronotoxicity" of seven metal compounds (Hg, Pb, Ni, Cr, Cu, Zn, or Fe) by assessing how their toxicity varies with circadian periodicity. Male ICR mice were injected with each metal compound intraperitoneally at 6 different time points over the course of a day (zeitgeber time [ZT]: ZT2, ZT6, ZT10, ZT14, ZT18 and ZT22). Mortality was then monitored until 14 days after the injection. Our investigation demonstrated that mice were tolerant against Ni toxicity during dark phase, on the other hand, they were tolerant against Cr toxicity during light phase. The chronotoxicity of Hg and Pb seemed to be biphasic. Further, mice were susceptible to toxicities against Cu and Zn in the time zone during which light and dark were reversed. Interestingly, no significant differences were observed for Fe exposure at any time of the day. Our results propose that the chronotoxicology may provide valuable information regarding the importance of injection timing for not only toxicity evaluation tests but also the reproducibility of animal experiments. Furthermore, our data suggests that chronotoxicology may be an important consideration when evaluating the quality of risk assessments for night shift workers who may be exposed to toxic substances at various times of the day.

Sasa veitchii extracts suppress acetaminophen-induced hepatotoxicity in mice

Background

The aim of this study was to investigate the therapeutic effects of a Sasa veitchii leaf extract (SE) on acetaminophen (APAP)-induced hepatotoxicity.

Methods

Seven-week-old male ddY mice were orally administered SE or saline (0.2 mL) once a day for a week. Twenty-four hours after the last pretreatment, the mice were intraperitoneally injected with 550 mg/kg APAP or saline under fasting conditions. The mice from each group were euthanized and bled for plasma analysis 2, 6, 24, and 72 h after the injection.

Results

We found that pretreatment with SE significantly decreased hepatic injury markers (i.e., alanine aminotransferase and aspartate aminotransferase), oxidative stress (malondialdehyde and glutathione level), inflammatory cytokines, histological damage, c-jun N-terminal kinase activation, and receptor-interacting protein-1 activation. Further, SE pretreatment decreased Cyp2e1 expression and increased total antioxidant capacity in the liver.

Conclusion

Our findings demonstrate that prophylactic SE treatment protects mice from APAP-induced hepatotoxicity through modulation of Cyp2e1 expression and antioxidant capacity.

Vitamin D3-induced hypercalcemia increases carbon tetrachloride-induced hepatotoxicity through elevated oxidative stress in mice

The aim of this study was to determine whether calcium potentiates acute carbon tetrachloride (CCl₄) -induced toxicity. Elevated calcium levels were induced in mice by pre-treatment with cholecalciferol (vitamin D3; V.D3), a compound that has previously been shown to induce hypercalcemia in human and animal models. As seen previously, mice injected with CCl₄ exhibited increased plasma levels of alanine aminotransferase, aspartate aminotransferase, and creatinine; transient body weight loss; and increased lipid peroxidation along with decreased total antioxidant power, glutathione, ATP, and NADPH. Pre-treatment of these animals with V.D3 caused further elevation of the values of these liver functional markers without altering kidney functional markers; continued weight loss; a lower lethal threshold dose of CCl₄; and enhanced effects on lipid peroxidation and total antioxidant power. In contrast, exposure to V.D3 alone had no effect on plasma markers of liver or kidney damage or on total antioxidant power or lipid peroxidation. The potentiating effect of V.D3 was positively correlated with elevation of hepatic calcium levels. Furthermore, direct injection of CaCl₂ also enhanced CCl₄-induced hepatic injury. Since CaCl₂ induced hypercalcemia transiently (within 3 h of injection), our results suggest that calcium enhances the CCl₄-induced hepatotoxicity at an early stage via potentiation of oxidative stress.

Sasa veitchii extract suppresses carbon tetrachloride-induced hepato- and nephrotoxicity in mice

OBJECTIVE

The aim of this study was to investigate the therapeutic effects of a Sasa veitchii leaf extract (SE) on carbon tetrachloride (CCl₄)-induced hepato- and nephrotoxicity.

METHODS

Seven-week-old male ddy mice were orally administered SE or saline for seven days. Twenty-four hours after the last SE or saline administration, the mice were intraperitoneally injected with 3 g/kg CCl₄ or olive oil. The mice from each group were euthanized and bled for plasma analysis 24 h after the CCl₄/olive oil injection.

RESULTS

We found that pretreatment with SE completely abolished the CCl₄-induced mortality in the mice after 24 h. The mice pretreated with SE exhibited significantly decreased levels of functional markers, and reduced histological damage in both the liver and the kidney. Furthermore, we found that the SE pretreatment decreased lipid peroxidation and calcium levels in the liver. Although SE could not induce the free radical-scavenging metallothioneins, the plasma biological antioxidant power was significantly increased in the mice pretreated with SE.

CONCLUSION

Our findings demonstrate that prophylactic treatment with SE protects mice from CCl₄-induced lethal toxicity by decreasing oxidative stress in the liver and kidney, presumably by increasing biological antioxidant power.