Halorotetin A: A Novel Terpenoid Compound Isolated from Ascidian Halocynthia rotetzi Exhibits the Inhibition Activity on Tumor Cell Proliferation

Dual green hemostatic sponges constructed by collagen fibers disintegrated from Halocynthia roretzi by a shortcut method

Recently, biomacromolecules have received considerable attention in hemostatic materials. Collagen, an ideal candidate for hemostatic sponges due to its involvement in the clotting process, has been facing challenges in extraction from raw materials, which is time-consuming, expensive, and limited by cultural and religious restrictions associated with traditional livestock and poultry sources. To address these issues, this study explored a new shortcut method that using wild Halocynthia roretzi (HR), a marine fouling organism, as a raw material for developing HR collagen fiber sponge (HRCFs), which employed urea to disrupt hydrogen bonds between collagen fiber aggregates. This method simplifies traditional complex manufacturing processes while utilized marine waste, thus achieving dual green in terms of raw materials and manufacturing processes. FTIR results confirmed that the natural triple-helical structure of collagen was preserved. HRCFs exhibit a blood absorption ratio of 2000-3500 %, attributed to their microporous structure, as demonstrated by kinetic studies following a capillary model. Remarkably, the cytotoxicity and hemolysis ratio of HRCFs are negligible. Furthermore, during in vivo hemostasis tests using rabbit ear and kidney models, HRCFs significantly reduce blood loss and shorten hemostasis time compared to commercial gelatin sponge and gauze, benefiting from the capillary effect and collagen's coagulation activity. This study provides new insights into the design of collagen-based hemostatic biomaterials, especially in terms of both raw material and green manufacturing processes.

Extraction, Isolation, Characterization, and Biological Activity of Sulfated Polysaccharides Present in Ascidian Viscera Microcosmus exasperatus

Ascidians are marine invertebrates that synthesize sulfated glycosaminoglycans (GAGs) within their viscera. Ascidian GAGs are considered analogues of mammalian GAGs and possess great potential as bioactive compounds, presenting antitumoral and anticoagulant activity. Due to its worldwide occurrence and, therefore, being a suitable organism for large-scale mariculture in many marine environments, our main objectives are to study Microcosmus exasperatus GAGs regarding composition, structure, and biological activity. We also aim to develop efficient protocols for sulfated polysaccharides extraction and purification for large-scale production and clinical applications. GAGs derived from M. exasperatus viscera were extracted by proteolytic digestion, purified by ion-exchange liquid chromatography, and characterized by agarose gel electrophoresis and enzymatic treatments. Anticoagulant activity was evaluated by APTT assays. Antitumoral activity was assessed in an in vitro model of tumor cell culture using MTT, clonogenic, and wound healing assays, respectively. Our results show that M. exasperatus presents three distinct polysaccharides; among them, two were identified: a dermatan sulfate and a fucosylated dermatan sulfate. Antitumoral activity was confirmed for the total polysaccharides (TP). While short-term incubation does not affect tumor cell viability at low concentrations, long-term TP incubation decreases LLC tumor cell growth/proliferation at different concentrations. In addition, TP decreased tumor cell migration at different concentrations. In conclusion, we state that M. exasperatus presents great potential as an alternative GAG source, producing compounds with antitumoral properties at low concentrations that do not possess anticoagulant activity and do not enhance other aspects of malignancy, such as tumor cell migration. Our perspectives are to apply these molecules in future preclinical studies for cancer treatment as antitumoral agents to be combined with current treatments to potentiate therapeutic efficacy.

Decanoic Acid Exerts Its Anti-Tumor Effects via Targeting c-Met Signaling Cascades in Hepatocellular Carcinoma Model

DA, one of the medium-chain fatty acids found in coconut oil, is suggested to have diverse biochemical functions. However, its possible role as a chemoprevention agent in HCC has not been deciphered. Aberrant activation of c-Met can modulate tumor growth and progression in HCC. Here, we report that DA exhibited pro-found anti-tumor effects on human HCC through the suppression of HGF/c-Met signaling cascades in vitro and in vivo. It was noted that DA inhibited HGF-induced activation of c-Met and its downstream signals. DA induced apoptotic cell death and inhibited the expression of diverse tumorigenic proteins. In addition, DA attenuated tumor growth and lung metastasis in the HCC mouse model. Similar to in vitro studies, DA also suppressed the expression of c-Met and its downstream signals in mice tissues. These results highlight the substantial potential of DA in the prevention and treatment of HCC.