8.1.8 Liver

Acetyl-11-keto-beta-boswellic acid (AKBA), a potent anti-inflammatory compound purified from Boswellia species, was investigated in a preclinical study for its potential in preventing and treating non-alcoholic fatty liver disease (NAFLD), the most common chronic inflammatory liver disorder. The study involved thirty-six male Wistar rats, equally divided into prevention and treatment groups. In the prevention group, rats were given a high fructose diet (HFrD) and treated with AKBA for 6 weeks, while in the treatment group, rats were fed HFrD for 6 weeks and then given a normal diet with AKBA for 2 weeks. At the end of the study, various parameters were analyzed including liver tissues and serum levels of insulin, leptin, adiponectin, monocyte chemoattractant protein-1 (MCP-1), transforming growth factor beta (TGF-β), interferon gamma (INF-ϒ), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α). Additionally, the expression levels of genes related to the inflammasome complex and peroxisome proliferator-activated receptor gamma (PPAR-ϒ), as well as the levels of phosphorylated and non-phosphorylated AMP-activated protein kinase alpha-1 (AMPK-α1) protein, were measured. The results showed that AKBA improved NAFLD-related serum parameters and inflammatory markers and suppressed PPAR-ϒ and inflammasome complex-related genes involved in hepatic steatosis in both groups. Additionally, AKBA prevented the reduction of the active and inactive forms of AMPK-α1 in the prevention group, which is a cellular energy regulator that helps suppress NAFLD progression. In conclusion, AKBA has a beneficial effect on preventing and avoiding the progression of NAFLD by preserving lipid metabolism, improving hepatic steatosis, and suppressing liver inflammation.

AIM: Acute kidney injury (AKI) is a sudden incident that is linked with a high lethality rate commonly due to distant organ injury. This study aims to explore the role of standardized Boswellia serrata (containing 35 % boswellic acid) in attenuating kidney and liver damage in a model of rats with renal insult.

MAIN METHODS: Sprague-Dawley rats, exposed to renal injury via ischemia-reperfusion model, were administered a daily regimen of 1000 or 2000 mg/kg Boswellia for seven days then rats were sacrificed on day eight. Alanine aminotransferase, aspartate aminotransferase, serum creatinine and blood urea nitrogen, were assayed. TLR9, oxidative stress markers; namely MDA and GSH, inflammatory cytokines; namely, IL-6, IL-1β, and TNF-α, as well as NF-κB were also measured.

KEY FINDINGS: Renal ischemia-reperfusion injury (IRI) impaired renal and liver function significantly, but Boswellia attenuated this impairment in a dose-dependent fashion. Histopathological assessment of kidney and liver confirmed that Boswellia decreased damage severity. A marked increase in TLR9, NF-κB, IL-6, IL-1β, TNF-α, and MDA besides decreased GSH levels were observed in the kidney and liver after renal IRI. Boswellia attenuated increases in TLR9, NF-κB, IL-1β, TNF-α, and IL-6 and boosted antioxidant defences via decreasing MDA and increasing GSH in kidney and liver. Anti-inflammatory and antioxidant effects of Boswellia were mostly comparable to those of silymarin.

SIGNIFICANCE: We conclude that the anti-inflammatory and antioxidant effects of Boswellia could be beneficial in ameliorating kidney and liver damage after AKI and that TLR9 might be the connection that signals liver injury in response to renal damage.

The hexane extract of oleo-gum-resin of Boswellia serrata (BSHE) was evaluated for its effect on liver injury induced by carbon tetrachloride, paracetamol or thioacetamide. The BSHE was given in two different doses (87.5 mg/kg p.o. and 175 mg/kg p.o.). Silymarin, a known hepatoprotective agent was used as standard. The lower dose of BSHE (87.5 mg/kg p.o.) significantly reduced the elevated levels of serum marker enzymes and prevented the increase in liver weight in all three models of liver injury, while the higher dose showed mild hepatoprotective activity. The hepatoprotective effect of lower dose of BSHE was supported by changes in histopathology. It was concluded that hexane extract of oleo-gum-resin of Boswellia serrata plant in lower doses possess hepatoprotective activity.

One hundred fifty-two methanol and water extracts of different parts of 71 plants commonly used in Sudanese traditional medicine were screened for their inhibitory effects on hepatitis C virus (HCV) protease (PR) using in vitro assay methods. Thirty-four extracts showed significant inhibitory activity (>/=60% inhibition at 100 microg/mL). Of these, eight extracts, methanol extracts of Acacia nilotica, Boswellia carterii, Embelia schimperi, Quercus infectoria, Trachyspermum ammi and water extracts of Piper cubeba, Q. infectoria and Syzygium aromaticum, were the most active (>/=90% inhibition at 100 microg/mL). From the E. schimperi extract, two benzoquinones, embelin (I) and 5-O-methylembelin (II), were isolated and found as potent HCV-PR inhibitors with IC(50) values of 21 and 46 microM, respectively. Inhibitory activities of derivatives of I against HCV-PR as well as their effects on other serine proteases were also investigated.