Freshwater snail extracts from *L. carinatus* and *B. unicolor* show selective anticancer and broad-spectrum antimicrobial activities
Background
The escalating crisis of antimicrobial resistance and the persistent challenge of cancer necessitate the discovery of novel therapeutic agents. Current treatments often face limitations such as severe side effects, drug resistance development, and insufficient efficacy against aggressive malignancies. Natural sources, particularly marine and freshwater organisms, are increasingly recognized as rich reservoirs of bioactive molecules, including peptides, with diverse pharmacological properties. Investigating underexplored species like freshwater snails offers a promising avenue to identify new compounds that could address critical gaps in antimicrobial and anticancer drug development.
Study Design
Researchers evaluated crude protein extracts from two Egyptian freshwater snails, Lanistes carinatus and Bellamya unicolor. The study assessed antioxidant enzyme activities, including superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST). Antimicrobial activity was tested against Escherichia coli, Staphylococcus aureus, Candida albicans, and Aspergillus niger. Cytotoxicity was evaluated against human cancer cell lines MCF-7 (breast), HeLa (cervical), HCT-116 (colorectal), and PC3 (prostate), alongside normal WI-38 cells (lung fibroblasts). Peptide composition was analyzed using LC-MS/MS to identify potential bioactive components.
Results
Both snail species exhibited low activities of antioxidant enzymes SOD, CAT, and GST, with L. carinatus showing slightly higher levels. Despite this, the crude protein extracts from both species significantly inhibited the growth of Escherichia coli and Staphylococcus aureus. L. carinatus extract demonstrated stronger antifungal activity against Candida albicans, while neither extract affected Aspergillus niger. Selective cytotoxicity was a key finding:
L. carinatus extract was most active against MCF-7 and HeLa cancer cells, whereas B. unicolor extract showed high potency against HCT-116 and moderate activity against PC3 cells. Crucially, both extracts displayed minimal effects on normal WI-38 cells, suggesting a favorable therapeutic index.
LC-MS/MSanalysis identified 26 short peptides, which are likely contributors to the observed antimicrobial and anticancer activities.
Key Findings
- L. carinatus and B. unicolor extracts inhibited Escherichia coli and Staphylococcus aureus growth.
- L. carinatus extract showed stronger antifungal activity against Candida albicans.
- L. carinatus extract was most active against
MCF-7andHeLacancer cells. - B. unicolor extract was highly potent against
HCT-116and moderately active againstPC3cancer cells. - 26 short peptides were identified via
LC-MS/MS, likely contributing to observed activities.
Why It Matters
This study provides compelling preliminary evidence that freshwater snails could be a novel source for bioactive peptides with therapeutic potential, particularly in the fight against antibiotic-resistant infections and various cancers. The observed selective cytotoxicity against cancer cells, sparing normal cells, is a critical indicator for potential drug development. While these are early in-vitro findings, they open the door for further isolation and characterization of the identified 26 short peptides, which could lead to new drug leads. Future research should focus on isolating and synthesizing these specific peptides to determine their individual efficacy and mechanism of action, moving towards in-vivo models and eventually clinical translation. This work highlights the importance of bioprospecting in underexplored natural environments for novel pharmaceutical compounds.
snail-extracts
bioactive-peptides
anticancer
antimicrobial
mcf-7
hela