Investigation of the possible mechanism of polysaccharides extracted from Leucocalocybe mongolica in exerting antitumor effects in H22 tumor‐bearing mice

Abstract

A response surface method was used to optimize the extraction of polysaccharides from Leucocalocybe mongolica. Moreover, the preliminary structural characteristics and antitumor activity of L. mongolica polysaccharide (LMP) were investigated. The results showed that the optimized extraction technological parameters for LMP were 93°C extraction temperature, 5 hr extraction time, and 30 ml/g liquid-to-solid ratio. The LMP content extracted under the optimal conditions was 6.64%. LC-MS/ MS results indicated that LMP is a neutral polysaccharide composed of d-fructose, d-mannose, dextrose anhydrate, d-xylose, trehalose, and galactose. The tumor inhibition rate was significantly improved by LMP treatment. LMP had minimal toxicity based on the significant decrease in AST and BUN levels; VEGF protein levels were also significantly decreased. In contrast, the levels of IFNγ, IL-2, IL-6, and TNFα were improved. The results of ELISA, H&E staining, TUNEL assay, immunohistochemistry, and western blotting indicated that the LMP exhibited antitumor activity in vivo by promoting apoptosis, mediating inflammatory responses, and inhibiting angiogenesis. Practical applicationsAs one of the main bioactive components, fungal polysaccharide has always been a hot research topic. Fungal polysaccharides are carbohydrate polymers composed of monosaccharide units bound together by glycosidic linkages, which have been found to be involved in many biological processes. In this research, the LMP structure was analyzed, and the immunohistochemical and western blot analysis confirmed that, LMP could effectively reduce the generation of tumor angiogenesis, promote apoptosis of tumor cell sand inhibit tumor growth. The results of this study can effectively provide a basis for clinical research and development of antitumor drugs, and lay a foundation for the study of the antitumor effects of wild edible and medicinal fungi.

Influence of Ethanol Extracts From Pholiota Adiposa on Gut Microbiota and Their Antitumor Properties in H22 Tumor-Bearing Mice

“…Ethanol (95%) was purchased from the Nanjing Chemical Reagents Co., Ltd. (Nanjing, China), and acetonitrile, methanol, and acetone were purchased from the Merck Company (chromatographic grade, Merck Company, Germany). Real-time PCR detector (LC96, Swiss) 10,47 was used.…”

“…EPA was then concentrated and freeze-dried. The nal crude extract (66.42 g) was stored at −20°C for further use 47 .…”

“…The ion scanning range was m/z 50-2000; the temperature of dissolution was 400 °C, the ow rate of the dissolvation gas was 800 L/h, low energy voltage was 6 eV, high energy voltage was 20-50 eV, ion source temperature was 120 °C, and capillary voltage was 2.5 kV. Then, the UPLC-QTOF-MSE mode was used to collect data, and Waters UNIFI software was used to analyze the results 47 .…”

“…All experimental procedures were strictly in accordance with the Regulations of Experimental Animal Administration issued by the Ethics committee for Laboratory Animals at the Jilin Agricultural University (Permit No. ECLA-JLAU-19036) 10,47 . And the statement in the attachment.…”

“…The control mice were intragastrically administered the same volume of saline solution, and the positive control was intraperitoneally injected with 25 mg/kg CTX. All groups of mice were treated once a day for 14 days 10,47 . Subsequently, all mice were euthanized that follow the AVMA Guidelines for Animal Euthanasia (2020) by intraperitoneal injection of barbiturate (180 mg/kg), and the tumor tissues were excised and weighed.…”