Morphometrical and Immunohistochemical Evaluation of Kidney as an Indirect Parameter to Estimate Age in Puppies in Veterinary Forensic Pathology

Estimation of age represents a central focus in the veterinary forensic pathology field. Currently, the visual examination of the dentition and the skeletal age are the main methods to estimate the age of puppies. Nevertheless, these methods are affected by a broad range of variables. In contrast, the kidney is characterized by a specific postnatal development. In human glomerulogenesis, fetal mesangial cells change their immunohistochemical phenotypes with maturation. Therefore, we hypothesized that histological and immunohistochemical examinations of the kidney can be used together as an indirect parameter for age determination in puppies' cadavers. Forty-five puppies' cadavers were divided into five groups defined by age (Group A= 0-15 days, Group B = 16-45 days, Group C = 46-85 days, Group D = 86-105 days, Group E= 105-365 days). For each case, kidney samples were collected and processed for histopathological (for morphometrical study of the glomerulus) and immunohistochemical (for the immunolocalization of the α-SMA protein) studies. Morphometrical study allowed us to observe statistical differences in the mean glomerulus numbers per field among assessed groups. Similarly, immunohistochemical examination showed differences in SMA expression among groups. Our findings suggest a potential use of kidney morphometrical and immunohistochemical examinations together as an indirect parameter to assess the age of illegally imported puppies.

Phenotypic Effects of Homeodomain-Interacting Protein Kinase 2 Deletion in Mice

Homeodomain-interacting protein kinase 2 (HIPK2) is a serine-threonine kinase that phosphorylates various transcriptional and chromatin regulators, thus modulating numerous important cellular processes, such as proliferation, apoptosis, DNA damage response, and oxidative stress. The role of HIPK2 in the pathogenesis of cancer and fibrosis is well established, and evidence of its involvement in the homeostasis of multiple organs has been recently emerging. We have previously demonstrated that Hipk2-null (Hipk2-KO) mice present cerebellar alterations associated with psychomotor abnormalities and that the double ablation of HIPK2 and its interactor HMGA1 causes perinatal death due to respiratory failure. To identify other alterations caused by the loss of HIPK2, we performed a systematic morphological analysis of Hipk2-KO mice. Post-mortem examinations and histological analysis revealed that Hipk2 ablation causes neuronal loss, neuronal morphological alterations, and satellitosis throughout the whole central nervous system (CNS); a myopathic phenotype characterized by variable fiber size, mitochondrial proliferation, sarcoplasmic inclusions, morphological alterations at neuromuscular junctions; and a cardiac phenotype characterized by fibrosis and cardiomyocyte hypertrophy. These data demonstrate the importance of HIPK2 in the physiology of skeletal and cardiac muscles and of different parts of the CNS, thus suggesting its potential relevance for different new aspects of human pathology.