Journal of Development in Bioengineering and Biosciences

This report critically evaluates the principal animal models used in antihypertensive drug development and the systematic factors underlying the persistent gap between preclinical efficacy and clinical outcomes. Three model systems are examined, the spontaneously hypertensive rat (SHR), the Dahl salt-sensitive rat, and renovascular (two-kidney and one-kidney one-clip) models, assessing their experimental utility, translational limitations, and ethical implications against human essential hypertension. Although each has yielded foundational mechanistic insight and supported major drug classes, their collective predictive validity is constrained by genetic homogeneity, the absence of common comorbidities (obesity, type 2 diabetes, chronic kidney disease), a pronounced bias toward male-only cohorts, short experimental timeframes, and interspecies divergence in key signalling pathways. Inconsistent experimental design, particularly blood-pressure measurement method and under-reporting of animal sex, further erodes reproducibility and cross-study synthesis. The report situates these issues within the global research landscape, highlighting geographic and ancestry-related blind spots that limit relevance to under-represented populations, and within the Three Rs and current UK/EU regulatory and data-protection frameworks. Emerging bridging strategies, CRISPR-Cas9 models incorporating human-relevant blood-pressure QTLs, iPSC-derived vascular constructs and vessel-on-chip systems, and multi-omics integration with human cohort data are evaluated as routes to reducing translational attrition. It concludes that closing the translational gap requires not only better models but mandatory sex-disaggregated design, rigorous transparent reporting, validated comorbid models, and reform of regulatory and ethical review, an institutional challenge as much as a scientific one.

Atrial fibrillation (AF), the most common cardiac arrhythmia links to significant morbidity, mortality, and healthcare costs through typical risks like ageing, hypertension, and structural heart disease. Recent studies show chronic psychosocial stress, negative emotions, and mental health factors in AF susceptibility. This review integrates AF epidemiology, focusing on mental stress and adverse emotional states interacts with atrial electrophysiology. Key mechanisms include sympathetic upregulation, parasympathetic attenuation, HPA axis overdrive, inflammation, and myocardial remodelling. Observational data associate persistent stress with higher AF incidence yet causation and stress reduction effectiveness remain uncertain. Targeting modifiable psychosocial factors mat contribute to improve risk stratification management and quality of life.

Preclinical drug development faces inherent limitations associated with conventional models, such as two-dimensional cell cultures and animal models, which exhibit limited physiological relevance and contribute to high attrition rates in clinical phases. NAMs, including human organoids, organ-on-chip systems, microphysiological platforms, physiologically based pharmacokinetic modeling, omics technologies, and artificial intelligence, provide an integrated and predictive framework for the assessment of organ-specific toxicities, mechanistic characterization, and human extrapolation. These tools enable dose optimization, improved risk monitoring, and reduction in animal use. Nevertheless, challenges remain regarding functional maturation, experimental reproducibility, regulatory validation, and population representativeness. The strategic and combined application of NAMs constitutes an advanced preclinical ecosystem that complements traditional approaches and holds significant potential to enhance the safety and efficacy of drug candidates in development.