Ethanol extracts collected from the <i>Styela clava</i> tunic alleviate hepatic injury induced by carbon tetrachloride (CCl₄) through inhibition of hepatic apoptosis, inflammation, and fibrosis

Abstract

The Styela clava tunic (SCT) is known as a good raw material for preparing anti-inflammatory compounds, wound healing films, guided bone regeneration, and food additives. To investigate whether ethanol extracts of the SCT (EtSCT) could protect against hepatic injury induced by carbon tetrachloride (CCl4) in ICR mice, alterations in serum biochemical indicators, histopathology, hepatic apoptosis, inflammation, and fibrosis were observed in ICR mice pretreated with EtSCT for 5 days before CCl4 injection. EtSCT contained 15.6 mg/g of flavonoid and 37.5 mg/g phenolic contents with high 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (93.3%) and metal chelation activity (46.5%). The EtSCT+CCl4-treated groups showed decreased levels of ALT, LDH, and AST, indicating toxicity and a necrotic area in the liver, while the level of ALP remained constant. The formation of active caspase-3 and enhancement of Bax/Bcl-2 expression was effectively inhibited in the EtSCT+CCl4-treated groups. Furthermore, the levels of pro- and anti-inflammatory cytokines and the phosphorylation of p38 in the TNF-α downstream signaling pathway rapidly recovered in the EtSCT+CCl4-treated groups. The EtSCT+CCl4-treated groups showed a significant decrease in hepatic fibrosis markers including collagen accumulation, MMP-2 expression, TGF-β1 concentration, and phosphorylation of Smad2/3. Moreover, a significant decline in malondialdehyde (MDA) concentration and enhancement of superoxide dismutase (SOD) expression were observed in the EtSCT+CCl4-treated groups. Taken together, these results indicate that EtSCT can protect against hepatic injury induced by CCl4-derived reactive intermediates through the suppression of hepatic apoptosis, inflammation, and fibrosis.

Bisphenol A Causes Liver Damage and Selectively Alters the Neurochemical Coding of Intrahepatic Parasympathetic Nerves in Juvenile Porcine Models under Physiological Conditions

“…For example, acetaminophen (paracetamol) is a common over the counter pain reliever, which may cause extensive hepatic trauma even after only a single over-exposure [ 27 ]. Environmental exposure to industrial toxins such as carbon tetrachloride (CCl4) has also been shown to cause vascular congestion and vacuolar degeneration [ 28 , 29 ]. Exposure of endogenous wildlife to a popular insecticide also caused observable hepatic damage in a similar way to that of CCl4 [ 30 ].…”

Isolation and Characterization of Polysaccharides from the Ascidian Styela clava

“…The polysaccharides isolated from the tunic may have been responsible for the bioactivities previously observed in extracts of S. clava , such as UV protection [ 11 ], prevention of hepatic injury [ 12 ], and anti-inflammatory effects [ 13 ]. Further work would be required to test the biological activity of the individual polysaccharides found.…”

“…Besides nanocellulose, S. clava contains other valuable compounds responsible for a range of observed bioactivities. In mice, ethanolic extracts of S. clava tunics have been shown to protect the skin from UV radiation [ 11 ] and the liver from hepatic injury [ 12 ], and aqueous extracts have displayed anti-inflammatory effects [ 13 ]. Enzymatic hydrolysates from S. clava have produced anti-inflammatory effects in zebrafish [ 14 ], in vitro antioxidant activity and growth inhibition of several cancer cell lines [ 15 ], and antihypertensive effects in patients with type 2 diabetes and hypertension [ 16 ].…”