A pseudoscorpion clinging to a cave salamander: phoresy or failed predation?

Posted by
  A pseudoscorpion clinging to a cave salamander: phoresy or failed predation? Abstract Pseudoscorpions are well known for phoretic associations with arthropods, but interactions with amphibians are rarely documented. Here we report a pseudoscorpion attached to the left palpebral region of an adult male Italian cave salamander, Speleomantes italicus , observed during a visual survey in a karst cave in Tuscany, Italy. The pseudoscorpion, assigned on the basis of visible morphology and locality to Chthonius cf. elongatus , was grasping a minute cutaneous fold on the lower margin of the left upper eyelid with one chela while the salamander moved slowly over the rock surface. No handling was performed and the initial contact between the two animals was not observed. The event therefore cannot be interpreted unambiguously, but may represent opportunistic phoresy or defensive attachment following a failed predation attempt. To our knowledge, this is the first published observation of a ...

Scorpion venom cytolytic peptide Smp43 induces caspase-dependent apoptosis in ovarian carcinoma cell line OVCAR-3

Posted by

 


Scorpion venom cytolytic peptide Smp43 induces caspase-dependent apoptosis in ovarian carcinoma cell line OVCAR-3

ABSTRACT

Ovarian cancer ranks as the sixth most prevalent type of gynecological cancer. Smp43, a cationic antimicrobial peptide isolated from the scorpion venom of Scorpio maurus palmatus, exhibits notable antibacterial, against both Gram-positive and Gram-negative bacteria, and antifungal activities. This study evaluates the anti-cancer efficacy of Smp43 and examines its effects on cell viability, cell cycle progression, apoptosis, necrosis, and oxidative stress in a human ovarian cancer cell line (OVCAR-3). Smp43 significantly reduced the viability of OVCAR-3 cells compared to the normal fibroblast cell line WI-38, with IC50 values of 7.75 µg/mL and 29.50 µg/mL, respectively. The peptide effectively caused G1 phase cell cycle arrest and apoptosis in OVCAR-3 cells. It modulated apoptotic markers by downregulating the pro-survival marker Bcl-2 while upregulating the pro-apoptotic markers Bax, p53, caspase-3, caspase-8, and caspase-9. Additionally, Smp43 significantly increased DNA fragmentation in OVCAR-3 cells and decreased antioxidant parameters. These findings suggest that Smp43 possesses potential anti-ovarian carcinoma properties, exerting its effects through mechanisms involving apoptosis induction, necrosis, G1 cell cycle arrest, and inhibition of the antioxidant defense system.

Hussein, S. I., Gerges, M. M., Al-Awadhi, R. M., Nafie, M. S., Abdel-Nabi, I. M., Sharma, P. P., & Abdel-Rahman, M. A. (2025). Scorpion venom cytolytic peptide Smp43 induces caspase-dependent apoptosis in ovarian carcinoma cell line OVCAR-3. Egyptian Journal of Basic and Applied Sciences, 12(1), 300–316. https://doi.org/10.1080/2314808X.2025.2555776