Anticancer potentiality and mode of action of low-carbohydrate proteins and peptides from mushrooms

Proteomic characterization and cytotoxic potential of proteins from Cuscuta (Cuscuta epithymum (L.) crude herbal product against MCF-7 human breast cancer cell line

BACKGROUND

The burden of breast cancer, the second leading cause of death worldwide, is increasing at an alarming rate. Cuscuta, used in traditional medicine for different ailments, including cancer, is known for containing phytochemicals that exhibit anticancer activity; however, the bioactivities of proteins from this plant remain unexplored. This study aimed to screen the cytotoxic potential of proteins from the crude herbal product of Cuscuta epithymum(L.) (CE) harvested from the host plants Alhagi maurorum and Medicago sativa.

METHODS

The proteins from CE were extracted using a salting-out method, followed by fractionation with a gel filtration chromatography column. Gel-free shotgun proteomics was subsequently performed for protein characterization. The viability assay using MTT was applied to deduce the cytotoxic potential of proteins against MCF-7 breast cancer cells, with further exploration of the effect of treatment on the expression of the apoptotic mediator BCL2-associated X protein (BAX) and B-cell lymphoma protein 2 (BCL-2) proteins, using western blotting to strengthen the findings from the in vitro viability assay.

RESULTS

The crude proteins (CP) of CE were separated into four protein peaks (P1, P2, P3, and P4) by gel filtration chromatography. The evaluation of potency showed a dose-dependent decline in the MCF-7 cell line after CP, P1, P2, and P3 treatment with the respective IC50 values of 33.8, 43.1, 34.5, and 28.6 µg/ml. The percent viability of the cells decreased significantly upon treatment with 50 µg/ml CP, P1, P2, and P3 (P < 0.001). Western-blot analysis revealed upregulation of proapoptotic protein BAX in the cells treated with CP, P3 (P < 0.01), and P2 (P < 0.05); however, the antiapoptotic protein, BCL-2 was downregulated in the cells treated with CP and P3 (P < 0.01), but no significant change was detected in P2 treated cells. The observed cytotoxic effects of proteins in the CP, P1, P2, and P3 from the in vitro viability assay and western blot depicted the bioactivity potential of CE proteins. The database search revealed the identities of functionally important proteins, including nonspecific lipid transfer protein, superoxide dismutase, carboxypeptidase, RNase H domain containing protein, and polyribonucleotide nucleotidyltransferase, which have been previously reported from other plants to exhibit anticancer activity.

CONCLUSION

This study indicated the cytotoxic activity of Cuscuta proteins against breast cancer MCF-7 cells and will be utilized for future investigations on the mechanistic effect of active proteins. The survey of CE proteins provided substantial data to encourage further exploration of biological activities exhibited by proteins in Cuscuta.

Current Advances in the Functional Genes of Edible and Medicinal Fungi: Research Techniques, Functional Analysis, and Prospects

Functional genes encode various biological functions required for the life activities of organisms. By analyzing the functional genes of edible and medicinal fungi, varieties of edible and medicinal fungi can be improved to enhance their agronomic traits, growth rates, and ability to withstand adversity, thereby increasing yield and quality and promoting industrial development. With the rapid development of functional gene research technology and the publication of many whole-genome sequences of edible and medicinal fungi, genes related to important biological traits have been mined, located, and functionally analyzed. This paper summarizes the advantages and disadvantages of different functional gene research techniques and application examples for edible and medicinal fungi; systematically reviews the research progress of functional genes of edible and medicinal fungi in biological processes such as mating type, mycelium and fruit growth and development, substrate utilization and nutrient transport, environmental response, and the synthesis and regulation of important active substances; and proposes future research directions for functional gene research for edible and medicinal fungi. The overall aim of this study was to provide a valuable reference for further promoting the molecular breeding of edible and medicinal fungi with high yield and quality and to promote the wide application of edible and medicinal fungi products in food, medicine, and industry.

Flammutoxin, a Degradation Product of Transepithelial Electrical Resistance-Decreasing Protein, Induces Reactive Oxygen Species and Apoptosis in HepG2 Cells

Proteins from Flammulina filiformis were prepared by sodium chloride extraction and fractionated by ammonium sulfate precipitation with increasing saturation degrees to obtain the protein fractions Ffsp-30, Ffsp-50, Ffsp-70, Ffsp-90, and Ffp-90. Among these protein fractions, Ffsp-50 possessed the most significant cytotoxic effect against three human gastrointestinal cancer cell lines, viz. HT-29, SGC-7901, and HepG2. SDS-PAGE and MALDI-TOF/TOF MS/MS analyses revealed that flammutoxin (FTX) was present as a dominating protein in Ffsp-50, which was further evidenced by HPLC-MS/MS determination. Furthermore, native FTX was purified from Ffsp-50 with a molecular weight of 26.78 kDa, exhibiting notable cytotoxicity against gastrointestinal cancer cell lines. Both Ffsp-50 and FTX exposure could enhance intercellular reactive oxygen species (ROS) generation and induce significant apoptosis in HepG2 cells. FTX was identified to be relatively conserved in basidiomycetes according to phylogenetic analysis, and its expression was highly upregulated in the primordium as well as the pileus of the fruiting body from the elongation and maturation stages, as compared with that in mycelium. Taken together, FTX could remarkably inhibit cell growth and induce ROS and apoptosis in HepG2 cells, potentially participating in the growth and development of the fruiting body. These findings from our investigation provided insight into the antigastrointestinal cancer activity of FTX, which could serve as a biological source of health-promoting and biomedical applications.

Nutritional Quality and Biological Application of Mushroom Protein as a Novel Protein Alternative

PURPOSE OF REVIEW

Global concerns about population growth, economic, and nutritional transitions and health have led to the search for a low-cost protein alternative to animal origins. This review provides an overview of the viability of exploring mushroom protein as a future protein alternative considering the nutritional value, quality, digestibility, and biological benefits.

RECENT FINDINGS

Plant proteins are commonly used as alternatives to animal proteins, but the majority of them are low in quality due to a lack of one or more essential amino acids. Edible mushroom proteins usually have a complete essential amino acid profile, meet dietary requirements, and provide economic advantages over animal and plant sources. Mushroom proteins may provide health advantages by eliciting antioxidant, antitumor, angiotensin-converting enzyme (ACE), inhibitory and antimicrobial properties over animal proteins. Protein concentrates, hydrolysates, and peptides from mushrooms are being used to improve human health. Also, edible mushrooms can be used to fortify traditional food to increase protein value and functional qualities. These characteristics highlight mushroom proteins as inexpensive, high-quality proteins that can be used as a meat alternative, as pharmaceuticals, and as treatments to alleviate malnutrition. Edible mushroom proteins are high in quality, low in cost, widely available, and meet environmental and social requirements, making them suitable as sustainable alternative proteins.

Edible mushroom industry in China: current state and perspectives

China is one of the largest producers and exporters of wild edible fungi in the world. Cultivation mushroom production value ranks within the top five after grain, vegetable, fruit, and edible oil plantation, greater than sugar, cotton, and tobacco business. More than 40 new varieties of high market value mushrooms from our group were highlighted in this article. Mushroom cultivations have a high impact on China's poverty alleviation program, with earnings at least ten times higher than rice and corn. The products were exported to 137 countries and regions, mainly to Japan, South Korea, ASEAN, the USA, and the European Union, among these, Japan is the biggest import market for cultivated mushrooms from China. Rapid development in the market and an increased demand for edible fungi generally enhance the economy of domestic edible fungi. We are the leading research group in logical farm design that is HACCP-certified to reduce the cost of investment for agriculture, thus broadening the consumption market of edible mushrooms and forming a demand-oriented leading industry for the promotion of human health. The enterprise needs to re-examine the operation plan and the strategic thinking to improve the fundamental drivers based on the available resources of the locality. Mushrooms growing intergrate with upgraded technologies and equipment to become smart agriculture which have smart production and intelligent factories. The purpose of suitable products will not change: delicious, nutritious, healthy, and modern. KEY POINTS: • Cultivation mushroom production value ranks within the top five after grain, vegetable, fruit, and edible oil plantation, greater than sugar, cotton, and tobacco business. • Mushroom cultivations have a high impact on China's poverty alleviation program, with earnings at least ten times higher than rice and corn. • The development of transportation and industrialization of mushrooms facilitate the modernization of mushroom industry in China.

St. George’s mushroom, Calocybe gambosa (Fr.) Donk: A promising source of nutrients and biologically active compounds

The composition of biologically active compounds of Calocybe gambosa (Lyophyllaceae) was analysed, and the antioxidant and cytotoxic activities were tested in vitro. C. gambosa was low in energy, fat, and carbohydrates, but rich in proteins and fibres. The total polyphenol content in the extracts was low (23.08 ± 0.67 in aqueous and 24.99 ± 4.25 μg GA mg−1 of extract in methanolic extract). The methanolic extract showed anti-DPPH radical activity with an IC50 of 626.10 ± 25.20 μg mL−1. The sample of C. gambosa is rich in nucleotides and amino acids responsible for its pleasant taste. The nucleoside and 5′-monophosphates contents were 0.97 mg g−1 and 2.32 mg g−1 of dry mushroom, respectively. The contents of essential and non-essential amino acids were 18.41 ± 0.06 and 41.75 ± 0.30 mg g−1 d.w., respectively. The percentages of saturated and unsaturated fatty acids were 42.6% and 57.4%, respectively. The most abundant water-soluble and fat-soluble vitamins were B1 and E, respectively. Cytotoxic effect of the extracts was examined against different cancer cell lines, and the best cytotoxicity was showed by the peptide extract against colon cancer cell line LS174.

Nutraceutical potential of mushroom bioactive metabolites and their food functionality

Numerous mushroom bioactive metabolites, including polysaccharides, eritadenine, lignin, chitosan, mevinolin, and astrakurkurone have been studied in life-threatening conditions and diseases such as diabetes, cardiovascular, hypertension, cancer, DNA damage, hypercholesterolemia, and obesity attempting to identify natural therapies. These bioactive metabolites have shown potential as antiviral and immune system strengthener natural agents through diverse cellular and physiological pathways modulation with no toxicity evidence, widely available, and inexpensive. In light of the emerging literature, this paper compiles the most recent information describing the molecular mechanisms that underlie the nutraceutical potentials of these mushroom metabolites suggesting their effectiveness if combined with existing drug therapies while discussing the food functionality of mushrooms. The findings raise hope that these mushroom bioactive metabolites may be utilized as natural therapies considering their therapeutic potential while anticipating further research designing clinical trials and developing new drug therapies while encouraging their consumption as a natural adjuvant in preventing and controlling life-threatening conditions and diseases. PRACTICAL APPLICATIONS: Diabetes, cardiovascular, hypertension, cancer, DNA damage, hypercholesterolemia, and obesity are among the world's largest life-threatening conditions and diseases. Several mushroom bioactive compounds, including polysaccharides, eritadenine, lignin, chitosan, mevinolin, and astrakurkurone have been found potential in tackling these diseases through diverse cellular and physiological pathways modulation with no toxicity evidence, suggesting their use as nutraceutical foods in preventing and controlling these life-threatening conditions and diseases.

Interrelationship among paraptosis, apoptosis and autophagy in lung cancer A549 cells induced by BEAP, an antitumor protein isolated from the edible porcini mushroom Boletus edulis

In today's world, cancer is still the leading cause of human death. Among them, the incidence and mortality of lung cancer remain high, and have become the focus of research in the world. BEAP, a protein with anti-lung cancer activity, was isolated and purified from the edible mushroom Boletus edulis. Previous studies have shown that BEAP can inhibit the proliferation of non-small cell lung cancer A549 cells by inducing apoptosis and cell cycle arrest in vitro and in vivo. However, there are many ways in which antitumor proteins from edible and medicinal mushroom play their roles. It is worth exploring whether there are other antitumor mechanisms of BEAP, which can provide reference value for the development of new drugs targeting non-small cell lung cancer and the repurposing of existing drugs.

Lactobionic acid-modified phycocyanin nanoparticles loaded with doxorubicin for synergistic chemo-photodynamic therapy

Phycocyanin (PC) is considered to be an effective natural photosensitizer, but it has not been well utilized as its inefficient biostability and intracellular accumulation. To overcome these limitations, the nano-sized PC particles (LAPC/DOX) were developed by grafting with lactobionic acid (LA) and loading with doxorubicin (DOX). Compared to the PC solution, the storage-stability and photostability of PC particles were remarkably increased, and the formation of nanoparticles further improved its biostability. Besides, CLSM images confirmed that LA could also enhance cellular uptake, resulting in more intracellular PC and DOX accumulation. MTT assay revealed that LAPC/DOX caused the highest cytotoxicity by combined chemo-photodynamic therapy. Finally, LAPC/DOX could efficiently accumulate and spread in tumoral multicellular spheroids, resulting in the enhanced growth inhibition. Overall, the LAPC/DOX is effective in cancer treatment, which provides new insights for the usage of functional proteins in vivo.