Structural entropy of liver sections in constant-light rats with aging-like features
In male Wistar rats kept under constant light for 3 months, structural entropy of liver sections rose 21.4% and correlated strongly with steatosis and circadian and senescence markers; the authors call it an exploratory index, not a validated biomarker of liver biological age. [1]
Automatic summary · not editorially reviewed
The key findings
Male Wistar rats (n = 120) were divided into a 12:12-hour light/dark control group and a constant-light group (24 hours per day, 3 months). [1]
Entropy increased by 21.4% and correlated strongly with steatosis score (r = 0.93) and inversely with melatonin (r = -0.81). [1]
Because aged comparator groups, melatonin replacement, recovery models and independent validation were lacking, entropy should not be considered a validated biomarker of biological liver age. [1]
The source at a glance
- Study type / format
- Preclinical animal experiment (abstract)
- Population / context
- Male Wistar rats (n = 120) under a 12:12-hour light/dark cycle or constant light for 3 months.
- Summary based on
- Study abstract
- Original publication
- August 31, 2026
Rat model: 3 months of constant light
The abstract describes male Wistar rats (n = 120) split into a control group with a 12:12-hour light/dark cycle and a constant-light group exposed to 24 hours of light per day for 3 months. Biochemical, histological, immunohistochemical and ultrastructural parameters were assessed. Shannon entropy was calculated on hematoxylin and eosin-stained sections using a graph-based approach based on the spatial distribution and size heterogeneity of nuclei. The stated aim was to test whether this entropy reflects tissue disorganization and how it relates to morphofunctional parameters of liver remodeling.
Supporting source [1]
Entropy up 21.4% and linked to steatosis
Constant light exposure caused a more than 2-fold decrease in serum melatonin, suppression of BMAL1 and CLOCK expression (3.7- and 3.5-fold), a rise in PER2 (+29.8%) and marked increases in p16 (23.8-fold), p21 (6.7-fold) and p53 (+80.9%), along with steatosis, hyperglycemia and mitochondrial dysfunction (fewer cristae, reduced circularity index). Entropy increased by 21.4% and correlated strongly with steatosis score (r = 0.93), p53-positive cells (r = 0.88) and PER2-positive cells (r = 0.86), and inversely with melatonin (r = -0.81). After adjustment for treatment, entropy remained associated with local morphological and ultrastructural parameters but not with systemic biochemical markers. An exploratory regression model, despite substantial multicollinearity, explained 87.5% of entropy variance.
Supporting source [1]
Exploratory index, not a validated age marker
The authors conclude that constant light induces liver changes sharing several features with aging-associated phenotypes, including steatosis, cellular senescence, mitochondrial dysfunction and circadian disruption. They describe structural entropy as an exploratory quantitative index of tissue disorganization that correlates with key morphofunctional parameters of liver remodeling. Because the study lacked aged comparator groups, melatonin replacement, recovery models and independent validation, they state that entropy should not be considered a validated biomarker of biological liver age. Its possible use in digital pathology and geroprotective research requires confirmation in future studies with appropriate designs.
Supporting source [1]
How to interpret this
Abstract only; the full text was not reviewed. This is a rat study without aged comparator groups, melatonin replacement, recovery models or independent validation, and the regression model showed substantial multicollinearity. Correlations are associations, not evidence of causation, and the findings do not establish human benefits.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Areshidze DA, Gladyshev NS, Kozlova MA, Anurkina AI. · europepmc.org · August 31, 2026