Metabolomic characterisation of the testis in Lysosomal Acid Lipase–deficient mice highlights age‑dependent changes in energy‑ and lipid‑associated metabolites

Metabolomic regulation is central to spermatogenesis, particularly due to metabolic support from Sertoli cells (SCs). Lysosomal acid lipase (LAL), encoded by the lipase A (LIPA) gene, participates in lysosomal lipid processing and may influence testicular metabolic homeostasis. This study explored genotype- and age-dependent testicular metabolomic alterations associated with LAL deficiency.

Testicular tissue from Lipa^-/-, Lipa^+/-, and wild-type mice was collected at 21, 70, and 150 days of age (n = 5–6/group/timepoint). Metabolomic profiling was performed using ¹H-NMR spectroscopy. Metabolite concentrations were normalized to tissue weight and auto-scaled prior to multivariate analysis. PCA by PERMANOVA with 999 permutations and sparse PLS-DA (5 components, 10 variables/component; performance evaluated using the platform’s performance module) were conducted in MetaboAnalyst 6.0. Differential metabolite levels were assessed using ordinary one-way ANOVA with uncorrected Fisher’s LSD for multiple comparisons in GraphPad Prism 10.3.1 and are reported as fold variation to control (wild-type) (mean ± SEM).

Genotype-dependent metabolic divergence was most pronounced at 21 days. Compared with wild-type, Lipa^-/- testes exhibited increased glycerol (1.42 ± 0.18-fold; p = 0.04), glycine (1.59 ± 0.27-fold; p = 0.008), succinate (1.68 ± 0.22-fold; p = 0.005), glutamate (1.56 ± 1.9-fold; p = 0.02), and acetate (1.98 ± 0.23-fold; p = 0.03). Lipa^+/- mice showed reduced succinate (0.53 ± 0.05-fold; p = 0.04), while taurine, succinate, and glutamate differed between heterozygotes and knockouts. At 150 days, Lipa^-/- mice showed reduced glycine and increased acetate, ethanolamine, and alanine; Lipa^+/- mice displayed elevated ethanolamine compared with controls and lower acetate and alanine than Lipa^-/- mice. Pathway analysis implicated pyruvate metabolism, glycolysis, and glycerophospholipid metabolism.

LAL deficiency is associated with sustained, genotype-dependent testicular metabolomic alterations involving energy-, amino-acid-, and lipid-related pathways. These findings support altered testicular metabolic homeostasis and warrant functional studies of lysosomal lipid handling and SC-germ-cell metabolic interactions.