Leonel Montealegre-Sánchez

Climate change affects health through direct, indirect, and socially mediated pathways, with consequences extending beyond morbidity and mortality. Objective: To analyze how the International Classification of Functioning, Disability and Health (ICF) can complement assessments of climate-related health impacts. Methods: A critical conceptual essay integrating normative documents and selected literature on climate, health, functioning, disability, climate justice, and disaster risk reduction. Results: A climate–functioning matrix comprising six dimensions is proposed: environmental hazard or exposure; exposure context; body functions, activities, and participation; environmental barriers and facilitators; temporality; and social and territorial inequalities. The matrix applies the ICF conceptual framework without modifying its categories or establishing causal relationships. Conclusion: Functioning broadens the analysis of climate-related health impacts by incorporating autonomy, everyday performance, and social participation. Its application in research, surveillance, and adaptation policy evaluation requires empirical validation and the meaningful participation of affected populations in its development and implementation across diverse settings. KEYWORDS: Climate Change; ICF; Persons with Disabilities; Disability Discrimination.

Objective: The expansion of human activities in northern Colombia has increased human-snake encounters, particularly with venomous Porthidium lansbergii lansbergii. Given the limited knowledge of systemic envenomation effects and previous studies focusing only on early murine symptoms, this investigation aimed to describe the time-course physiopathology of P. lansbergii lansbergii envenomation following intramuscular injection in vivo. Methods: Venom was inoculated in the gastrocnemius muscles of Swiss Webster mice, and blood, urine, and tissue samples were taken at different times to evaluate lethality and biochemical markers of renal function and oxidative stress. Results: This study reports the first intramuscular LD₅₀ for P. lansbergii lansbergii venom at 24.83 mg/Kg. Administering 80% of this LD₅₀ induced early signs of renal injury, evidenced by urinary biomarkers over 24 h. The antioxidant activity was found at low levels in kidney tissue throughout the evaluated time post-envenomation. Malondialdehyde activity increased at the earliest point, while proinflammatory activity increased later. Urine metabolomics revealed elevated taurine and allantoin in the envenomed groups. Discussion: Compensatory mechanisms in response to oxidative stress and tissue damage induced by the venom were evident in the envenomed mice over the evaluated time. However, histological analysis revealed evidence of pro-inflammatory processes occurring only at early times. Metabolomic analyses of urine samples identified taurine as a potential early biomarker of elevated oxidative stress and protein and creatinine levels. Conclusions: P. lansbergii lansbergii venom induces alterations in murine renal tissue, affecting urinary biomarkers of kidney function within hours post-envenomation. Delayed proinflammatory effects may suggest an antioxidant imbalance in the envenomed mice, with unknown long-term effects. Further research on the role of oxidative stress and inflammation in renal structure and function following envenomation is necessary, emphasizing the need for prompt clinical management.

The antitumor potential of proteins from snake venoms has been studied in recent decades, and evidence has emerged that phospholipases A₂ can selectively attack cells of various types of tumors. Previous results have shown that phospholipase A₂ “Pllans-II,” isolated from Porthidium lansbergii lansbergii snake venom, displayed antitumoral activity on cervical cancer and did not alter the viability of non-tumorigenic cells. However, until now, there was no evidence of its safety at the local and systemic levels, nor had experiments been developed to demonstrate that its production using recombinant technology allows us to obtain a molecule with effects similar to those generated by native phospholipase. Thus, we evaluated the impact caused by Pllans-II on murine biomodels, determining whether it induced local hemorrhage or increased pro-inflammatory and liver damage markers and histological alterations in the liver and kidneys. Additionally, the protein was produced using recombinant technology using a pET28a expression vector and the BL21 (DE3) Escherichia coli strain. Equally, its enzymatic activity and anticancer effect were evaluated on cervical cancer lines such as HeLa and Ca Ski. The results demonstrated that Pllans-II did not generate hemorrhagic activity, nor did it increase the pro-inflammatory cytokines IL-6, IL-1B, or TNF-α at doses of 3.28, 1.64, and 0.82 mg/kg. There was also no evidence of organ damage, and only ALT and AST increased in mild levels at the two highest concentrations. Additionally, the recombinant version of Pllans-II showed conservation in its catalytic activity and the ability to generate death in HeLa and Ca Ski cells (42% and 23%, respectively). These results demonstrate the innocuity of Pllans-II at the lowest dose and constitute an advance in considering a molecule produced using recombinant technology a drug candidate for selective attacks against cervical cancer.

Despite advances in chemotherapeutic drugs used against cervical cancer, available chemotherapy treatments adversely affect the patient’s quality of life. For this reason, new molecules from natural sources with antitumor potential and few side effects are required. In previous research, Pllans−II, a phospholipase A₂ type-Asp49 from Porthidium lansbergii lansbergii snake venom, has shown selective attack against the HeLa and Ca Ski cervical cancer cell lines. This work suggests that the cytotoxic effect generated by Pllans−II on HeLa cells is triggered without affecting the integrity of the cytoplasmic membrane or depolarizing the mitochondrial membranes. The results allow us to establish that cell death in HeLa is related to the junction blockage between α₅β₁ integrins and fibronectin of the extracellular matrix. Pllans−II reduces the cells’ ability of adhesion and affects survival and proliferation pathways mediated by intracellular communication with the external environment. Our findings confirmed Pllans−II as a potential prototype for developing a selective chemotherapeutic drug against cervical cancer.

Due to the lack of chemotherapeutic drugs that selectively affect cervical cancer cells, natural sources such as snake venom are currently being investigated for molecules with antitumor potential. Pllans–II, a phospholipase A₂ type–Asp49 from Porthidium lansbergii lansbergii snake venom, induced cell death in a cervical cancer cell line—Ca Ski—related to dysfunction in the ability to resolve endoplasmic reticulum stress, evidenced by sub–expression of genes such as PERK, ERO1 PDIs, HSP70, and CHOP. Western blot analysis validated the last two genes′ sub–expression at the protein level. In addition, Pllans–II presented a dose–dependent cytotoxic effect on cancer cells and an insignificant effect on healthy endothelial cells (HUVEC). Additionally, Pllans–II inhibited cancer cells′ adhesion and migration capacity, induced cell cycle arrest in the G2/M phase, and induced apoptosis stimulated possibly by the extrinsic route. These results demonstrate for the first time that Pllans–II has an antitumor effect on a squamous epithelial cervical cancer cell line and represents a possible biotechnological tool for designing a prominent antitumor agent.

Cervical cancer is the fourth most common cancer worldwide in women. Apoptosis reactivation has become the main strategy for decreasing cancer proliferation. There is a need to extend the search for new drugs to implement more effective and less toxic strategies for cervical cancer treatment. Research has been carried out to find new drugs that have minimal side effects and that focus on the tumor microenvironment, particularly in the induction of cellular apoptosis and cell migration and the inhibition of angiogenesis. Potent toxins from snake venoms have shown potential as sources for the synthesis of new drugs with such characteristics. The present work aimed to describe cervical cancer characteristics, associated risk factors, current treatments and to highlight the effects of toxins isolated from the venom of snakes of the Viperidae family on cervical cancer cell lines.