Experimental and Toxicologic Pathology最新文献

Biliary fibrosis is a complex process in which macrophages and myofibroblasts may play central roles. We investigated biliary fibrosis lesions induced in the Glisson’s sheath in rats by alpha-naphthylisothiocyanate (ANIT) administration under macrophage depletion. Hepatic macrophages were depleted in F344 rats with liposome-encapsulated clodronate (CLD) (10 mL/kg body weight, i.v) followed by bile duct injury with ANIT (75 mg/kg body weight, i.p) (ANIT + CLD group). Rats received empty-liposomes (Lipo) followed by ANIT, and served as control (ANIT + Lipo group). In both ANIT + Lipo and ANIT + CLD groups, ANIT-induced bile duct injury with inflammatory cell infiltration was seen on days 1–3, and subsequently reparative fibrosis occurred on days 5 and 7. In comparisons between the two groups, macrophages reacting to CD68, CD163, MHC class II and CD204 were less in numbers in ANIT + CLD group; the most sensitive immunophenotype was of CD163-positive. Furthermore, in ANIT + CLD group interstitial mesenchymal cells/myofibroblasts reacting to vimentin, desmin and α-smooth muscle actin were also less in grades and tended to be delayed in appearance. Interestingly, MCP-1, IFN-γ, IL-10, and TGF-β1 mRNAs were significantly increased mainly on day 2 in ANIT + Lipo group, while the levels of these factors were prominently lower in ANIT + CLD group. Collectively, depletion of hepatic macrophages plays roles in attenuating biliary fibrogenesis by production of inflammatory factors. The present results indicated clearly importance of macrophage functions in the pathogenesis of biliary fibrosis.

Context

The Viperidae family venom is a rich source of bioactive compounds such as many proteases, which cause tissue necrosis and affect mostly the vascular system. However, the venom exhibits therapeutic potentials and has contributed to the development of some medical drugs. Specifically, the Montivipera bornmuelleri venom has shown to exhibit antibacterial, pro-inflammatory and antifungal activities.

Objective

This work evaluates the cytotoxic effect of the M. bornmuelleri venom on human-derived keratinocytes including the non-tumorigenic HaCaT, the benign A5 and the low-grade malignant II4 cells.

Materials and methods

The toxicity of different venom concentrations (0.9, 1.87, 3.75, 7.5, 15, 30 and 60 μg/mL) and their effect on the viability of the cells lines were assessed using the Lactate Dehydrogenase (LDH) activity and the Trypan blue tests after 24 h of incubation.

Results

The venom was able to reduce the viability of all cell lines in a dose dependent manner with the HaCat cells being the least affected. For example, the 60 μg/mL dose induced a more significant decrease the viability of A5 (44%) and II4 (21.33%) keratinocytes as compared to HaCaT cells (70.63%). Also, this venom showed a higher cytotoxic activity on the A5 (52.45%) and II4 (98.67%) cells as compared to HaCaT cells (30.14%) with an IC₅₀ estimated at 10 μg/mL on II4 and at 60 μg/mL on benign A5.

Discussion and conclusion

Those differential cytotoxic effects of the M. bornmuelleri venom pave the road for more advanced studies which might unravel the potential anticancer effects of this venom.

Radix Sophorae tonkinensis (S. tonkinensis) is used in Chinese folk medicine to treat sore throats, viral hepatitis, and jaundice. However, little is known about the hepatotoxicity induced by it. This study is to investigate hepatotoxicity induced by radix S. tonkinensis and a potential supplemental biomarker for liver injury through acute toxicity, accumulative toxicity, tolerance test, and sub-chronic toxicity. The contents of cytisine (CYT), matrine (MT), and oxymatrine (OMT) in radix S. tonkinensis extracts were determined simultaneously by the method we developed. In the acute toxicity study, mice were scheduled for single oral gavage at doses of 0, 2.4, 3.2, 4.2, 5.6, 7.5 g/kg of radix S. tonkinensis extracts respectively. Another three groups of mice received radix S. tonkinensis extracts orally in single doses of 0, 4.3, 5.6 g/kg, while the two groups of the hepatic injury model were induced by intraperitoneal injection with 0.1% and 0.2% carbon tetrachloride (CCl₄). Mortality rate, analysis of serum biochemistry, and histopathological examination were used to assess the acute toxicity. In the accumulative toxicity study, mice were treated radix S. tonkinensis extracts orally by the method of dose escalation for 20 days respectively. Accumulative toxicity was assessed by mortality rate. In the tolerance test, half of the mice of test group in the accumulative toxicity were administered the dose of 4.3 g/kg radix S. tonkinensis extracts, and the rest of the mice in the test group were assigned to receive the dose of 5.6 g/kg radix S. tonkinensis extracts. In the sub-chronic toxicity study, mice were treated with daily doses of 0, 0.25, 1.0, 2.5 g/kg radix S. tonkinensis extracts for 90 days. Assessments of body weights, serum biochemical analysis, and histopathological examination were performed. An enzyme-inhibition assay for butyrylcholinesterase (BuChE) and acetylcholinesterase (AChE) of CYT, MT, and OMT was also carried out. The contents of CYT, MT, and OMT in radix S. tonkinensis extracts were 5.63 mg/g, 27.63 mg/g, and 16.20 mg/g respectively. In the acute toxicity study, LD50 of radix S. tonkinensis extracts was 4.3 g/kg. No mice were found dead in the accumulative toxicity study. In the acute toxicity and tolerance test, increased ALT, AST, and CHE levels were observed in a dose-response manner, while the severity of histological changes in liver was shown in a dose-dependent mode. In the sub-chronic toxicity, though there was a decline trend of ALT and AST levels found in 0.25 g/kg, 1.0 g/kg, and 2.5 g/kg radix S. tonk