In vivo hepatoprotective effect of Morinda elliptica stem extract against liver fibrosis induced by thioacetamide

Morinda elliptica L. (Rubiaceae) is a phytomedicinal herb, used to treat gastrointestinal complications in Peninsular Malaysia. The study evaluates the in vivo hepatoprotective activity of ethanolic extract of M. elliptica stem in thioacetamide (TAA) induced liver fibrosis in male Sprague Drawly rats. Thirty adult rats were divided into five groups of six rats each. Rats of the normal control group received intraperitoneal injections (i. p.) of vehicle 10% Tween-20, 5 ml/kg, and hepatotoxic group 200 mg/kg TAA three times per week respectively. Three supplementary groups were treated with TAA plus daily oral silymarin (50 mg/kg) or M. elliptica (250 or 500 mg/kg). After 8 weeks of treatment, all rats were sacrificed. Liver fibrosis was assessed by gross macroscopic and microscopic tissue analysis, histopathological, and biochemical analysis. The livers of the TAA treated group showed uniform coarse granules, hepatocytic necrosis with lymphocytes infiltration. Contrary, the livers of M. elliptica treated groups (250 and 500 mg/kg) were much smoother and the cell damage was much lesser. The livers of M. elliptica treated groups rats showed elevated activity of SOD and CAT with a significant decrease in MDA level at p < .0001. The level of liver damage parameters, that is, ALP, ALT, and AST, bilirubin, total protein, and albumin were restored to the normal comparable to silymarin. M. elliptica stem extract significantly promoted normal rat liver architecture with significant perfections in biochemical parameters. The molecular contents of M. elliptica with hepatoprotective influence could be discovered, is the future prospective of this study.

Hepatoprotectivity of Panduratin A against liver damage: In vivo demonstration with a rat model of cirrhosis induced by thioacetamide

This experiment evaluated Panduratin A (PA), a chalcone isolated from Boesenbergia rotunda rhizomes, for its hepatoprotectivity. Rats were subjected to liver damage induced by intra-peritoneal injection of thioacetamide (TAA). PA was tested first for its acute toxicity and then administered by oral gavage at doses 5, 10, and 50 mg/kg to rats. At the end of the 8^th week, livers from all rats were excised and evaluated ex vivo. Measurements included alkaline phosphatase (AP), alanine transaminase (ALT), aspartate transaminase (AST) and gamma-glutamyl transferase (GGT), serum platelet-derived growth factor (PDGF) and transforming growth factor (TGF-β1), and hepatic metalloproteinase enzyme (MMP-2) and its inhibitor extracellular matrix protein (TIMP-1). Oxidative stress was measured by liver malondialdehyde (MDA) and nitrotyrosine levels, urinary 8-hydroxy 2- deoxyguanosine (8-OH-dG), and hepatic antioxidant enzyme activities. The immunohistochemistry of TGF-β₁ was additionally performed. PA revealed safe dose of 250 mg/kg on experimental rats and positive effect on the liver. The results suggested reduced hepatic stellate cells (HSCs) activity as verified from the attenuation of serum PDGF and TGF-β1, hepatic MMP-2 and TIMP-1, and oxidative stress. The extensive data altogether conclude that PA treatment could protect the liver from the progression of cirrhosis through a possible mechanism inhibiting HSCs activity.

The apoptotic effects of Brucea javanica fruit extract against HT29 cells associated with p53 upregulation and inhibition of NF-κB translocation

Background

Brucea javanica (L.) Merr. is a plant from the genus Brucea, which is used in local traditional medicine to treat various diseases. Recent studies revealed an impressive anticancer efficiency of B. javanica extract in different types of cancer cells.

Purpose

In this study, we have investigated the cytotoxic effects of the B. javanica hexane, ethanolic extracts against colon cancer cells. HT29 colon cells were selected as an in vitro cancer model to evaluate the anticancer activity of B. javanica ethanolic extract (BJEE) and the possible mechanisms of action that induced apoptosis.

Methods

3-(4,5-dimethylthiazol-2-yl)-2, 5,-diphenyltetrazolium bromide (MTT), lactate dehydrogenase, acridine orange/propidium iodide, and annexin-V-fluorescein isothiocyanate assays were performed to determine the antiproliferative and apoptosis validation of BJEE on cancer cells. Measurement of reactive oxygen species (ROS) production, caspase activities, nucleus factor-κB activity, and gene expression experiments was done to investigate the potential mechanisms of action in the apoptotic process.

Results

The results obtained from this study illustrated the significant antiproliferative effect of BJEE on colorectal cancer cells, with a concentration value that inhibits 50% of the cell growth of 25±3.1 µg/mL after 72 h of treatment. MTT assay demonstrated that the BJEE is selectively toxic to cancer cells, and BJEE induced cell apoptosis via activation of caspase-8 along with modulation of apoptosis-related proteins such as Fas, CD40, tumor necrosis factor-related apoptosis-inducing ligands, and tumor necrosis factor receptors, which confirmed the contribution of extrinsic pathway. Meanwhile, increased ROS production in treated cells subsequently activated caspase-9 production, which triggered the intrinsic pathways. In addition, overexpression of cytochrome-c, Bax, and Bad proteins along with suppression of Bcl-2 illustrated that mitochondrial-dependent pathway also contributed to BJEE-induced cell death. Consistent with the findings from this study, BJEE-induced cancer cell death proceeds via extrinsic and intrinsic mitochondrial-dependent and -independent events.

Conclusion

From the evidence obtained from this study, it is concluded that the BJEE is a promising natural extract to combat colorectal cancer cells (HT29 cells) via induction of apoptosis through activation of extrinsic and intrinsic pathways.

Septicaemia models using Streptococcus pneumoniae and Listeria monocytogenes: understanding the role of complement properdin

Streptococcus pneumoniae and Listeria monocytogenes, pathogens which can cause severe infectious disease in human, were used to infect properdin-deficient and wildtype mice. The aim was to deduce a role for properdin, positive regulator of the alternative pathway of complement activation, by comparing and contrasting the immune response of the two genotypes in vivo. We show that properdin-deficient and wildtype mice mounted antipneumococcal serotype-specific IgM antibodies, which were protective. Properdin-deficient mice, however, had increased survival in the model of streptococcal pneumonia and sepsis. Low activity of the classical pathway of complement and modulation of FcγR2b expression appear to be pathogenically involved. In listeriosis, however, properdin-deficient mice had reduced survival and a dendritic cell population that was impaired in maturation and activity. In vitro analyses of splenocytes and bone marrow-derived myeloid cells support the view that the opposing outcomes of properdin-deficient and wildtype mice in these two infection models is likely to be due to a skewing of macrophage activity to an M2 phenotype in the properdin-deficient mice. The phenotypes observed thus appear to reflect the extent to which M2- or M1-polarised macrophages are involved in the immune responses to S. pneumoniae and L. monocytogenes. We conclude that properdin controls the strength of immune responses by affecting humoral as well as cellular phenotypes during acute bacterial infection and ensuing inflammation.