"I Miss My Liver." Nonmedical Sources in the History of Hepatocentrism

Compartmentalization, cooperation, and communication: The 3Cs of Hepatocyte zonation

The unique architecture of the liver allows for spatial compartmentalization of its functions, also known as liver zonation. In contrast to organelles and cells, this compartment is devoid of a surrounding membrane, rendering traditional biochemical tools ineffective for studying liver zonation. Recent advancements in tissue imaging and single-cell technologies have provided new insights into the complexity of tissue organization, rich cellular composition, and the gradients that shape zonation. Hepatocyte gene expression profiles and metabolic programs differ based on their location. Non-parenchymal cells further support hepatocytes from different zones through local secretion of factors that instruct hepatocyte activities. Collectively, these elements form a cohesive and dynamic network of cell-cell interactions that vary across space, time, and disease states. This review will examine the cell biology of hepatocytes in vivo, presenting the latest discoveries and emerging principles that govern tissue-level and sub-cellular compartmentalization.

The prothrombotic tendency of metabolic-associated fatty liver disease

Our understanding of the function of the liver has evolved over the centuries. Early theories proposing that the liver could be used to divine the future have been superseded by our current knowledge of the importance of the liver in processes such as digestion and detoxification. Similarly, although liver disease was previously associated with only an increased risk of bleeding, there is now a substantial body of evidence demonstrating an increased thrombotic potential in patients with this disease. Metabolic-associated fatty liver disease (MAFLD) is increasing in frequency and is likely to overtake alcoholic liver disease as the primary indication for liver transplant in the future. In this review, we discuss the evidence linking liver disease, and MAFLD in particular, with arterial and venous thromboembolic disease. We review the safety and efficacy of anticoagulation in advanced liver disease and consider whether antithrombotic agents could slow or halt the progression of fibrosis in MAFLD.

Gaspare Aselli (1581-1625) and Lacteis Venis: Four Centuries From the Discovery of Lymphatic System

The first half of the seventeenth century may be seen as the turning point of knowledge of human anatomy and physiology, as also demonstrated by the works by William Harvey (1578-1657) on the circulation of the blood. This article aims to present biographic context of the surgeon Gaspare Aselli (1581-1625) and his rather fortuitous discovery of the lacteals in Milan in 1622, that contributed to the comprehension of the lymphatic system. The experimentation on living animals (anatomia animata, living anatomy), and particularly the vivisection used by Gaspare Aselli provided the basis for much of the subsequent investigation of the human physiology. In particular, the discovery of lymphatics challenged the basis of the Galenic doctrine, denying the liver the central role it had formerly been granted in transforming food into blood and revolutionized the ancient hepatocentrism in favor of the modern concept of cardiocentrism.

Giovanni Maria Lancisi (1654-1720) and the modern cardiovascular physiology

Giovanni Maria Lancisi (1654-1720) was one of the most important Italian physicians of the modern age. Orphaned of his mother, he spent his early years in the city of Orvieto; when he was 12, his father brought him back to Rome and enrolled him to study medicine at the Sapienza University in Rome. His dedication to study and work soon led him to increasingly important positions. Within a few years, the fame of Lancisi became such that he was appointed the personal physician of three popes. In De Subitaneis Mortibus (1707), he described the pathophysiology of heart diseases, identifying the cause of sudden deaths in structural anomalies of the heart, lungs, and brain. He also wrote about cerebral localizations and first discussed the physiological mechanisms of urine formation and excretion. In 1717, Lancisi described the pathogenesis of malaria and the close correlation between its onset and the swampy waters of the Tiber River, proposing the draining of marshes to eradicate malaria. In the posthumous De Motu Cordis et Aneurysmatibus (1728) he described for the first time heart dilatation and aneurysms of the great vessels, providing a fundamental contribution to the history of cardiovascular physiology. Proof of his interest in medical education is the establishment of an academy and the donation of a library to the hospital, bridging the gap between theory and practice in medical training. Over the centuries, Lancisi's memory has faded, but his work is still relevant for anyone practicing the medical profession.

From sadness to stiffness: the spleen's progress

The spleen is a lymphoid organ that has been poorly studied compared to other solid organs, probably because it has been considered a useless and unnecessary part of the body. For many centuries it has been considered a mysterious organ with uncertain functions. The first descriptions of the spleen date back to ancient ages. The spleen has been considered as a reservoir of liquids, strictly linked to stomach digestion, and in different cultures, it has been linked to melancholy and sadness due to the accumulation of black bile (humoral doctrine). A detailed anatomic description was first made by Vesalius during the Renaissance, and further implemented with the description of its microscopic structure by Marcello Malpighi in the seventeenth century. The first case reports regarding spleen functions and pathology regarded common causes of splenomegaly, such as malaria infection, and traumatic rupture. At the beginning of the last century, the pivotal concepts of hypo- and hypersplenism were introduced, along with the cumulating evidence of the relation between spleen removal and increased susceptibility to infections and thromboembolism. The study of hyposplenic states, which occur much more commonly than originally thought in many immune-mediated disorders, has rapidly increased after the validation of a simple method for assessing spleen function, namely pitted red cell count. In recent years, spleen morphology, in particular spleen stiffness, has been proposed as a marker of portal hypertension. In this paper, we retrace the fundamental steps of the discovery of the functions of the spleen.