Differential Diagnosis of Hepatic Necrosis Encountered at Autopsy

Lipid-lowering, anti-inflammatory, and hepatoprotective effects of isorhamnetin on acetaminophen-induced hepatotoxicity in mice

Isorhamnetin is a hepatoprotective flavonoid molecule derived from the leaves and fruits of Hippophae rhamnoides L. However, the protective effect of isorhamnetin on acetaminophen (APAP) induced hepatotoxicity is still unknown. Thus, we aimed to investigate the lipid-lowering, anti-inflammatory, and hepatoprotective effects of isorhamnetin on APAP-induced hepatotoxicity in mice. Hepatotoxicity was induced by a single injection of APAP (300 mg/kg, intraperitoneally). Isorhamnetin (50 or 100 mg/kg, orally) and N-acetylcysteine (NAC) (200 mg/kg, orally), or vehicle control, were administered 1 h before the administration of APAP. Total antioxidant status (TAS) and total oxidative status (TOS) of liver tissue and levels of inflammatory factors (TNF-α, IL-1β, and IL-6) were analyzed by ELISA. Lipid profiles and liver function parameters were measured using an autoanalyzer. In addition, liver tissue was examined histopathologically. Isorhamnetin treatment significantly reduced the APAP-induced increase in the liver weight and liver index; it also reduced the APAP-induced increase in serum liver parameters (ALT, AST, ALP, and LDH) (p < 0.05). Isorhamnetin significantly reduced APAP-induced oxidative stress and inflammation by increasing TAS levels and decreasing TOS, TNF-α, IL-1β, and IL-6 levels (p < 0.05). Moreover, isorhamnetin treatment significantly regulated lipid profiles (TG, T-C, LDL-C, and HDL-C levels) that changed in response to APAP administration (p < 0.05). In histopathological examination, liver degeneration observed in the APAP group was significantly reduced in the NAC and isorhamnetin-treated groups (p < 0.05). This study suggests that isorhamnetin has a significant protective effect on APAP-induced hepatotoxicity in mice through its lipid-lowering, antioxidant, and anti-inflammatory effects.

Inflammation: A New Look at an Old Problem

Pro-inflammatory stress is inherent in any cells that are subject to damage or threat of damage. It is defined by a number of universal components, including oxidative stress, cellular response to DNA damage, unfolded protein response to mitochondrial and endoplasmic reticulum stress, changes in autophagy, inflammasome formation, non-coding RNA response, formation of an inducible network of signaling pathways, and epigenetic changes. The presence of an inducible receptor and secretory phenotype in many cells is the cause of tissue pro-inflammatory stress. The key phenomenon determining the occurrence of a classical inflammatory focus is the microvascular inflammatory response (exudation, leukocyte migration to the alteration zone). This same reaction at the systemic level leads to the development of life-critical systemic inflammation. From this standpoint, we can characterize the common mechanisms of pathologies that differ in their clinical appearance. The division of inflammation into alternative variants has deep evolutionary roots. Evolutionary aspects of inflammation are also described in the review. The aim of the review is to provide theoretical arguments for the need for an up-to-date theory of the relationship between key human pathological processes based on the integrative role of the molecular mechanisms of cellular and tissue pro-inflammatory stress.

Liver biopsy for assessment of chronic liver diseases: a synopsis

The world-wide increase in chronic liver disease (CLD) calls for refinement of diagnostic and prognostic measures for early and accurate disease detection and management. Regardless of the aetiology, liver biopsy allows direct visualisation of specimen under the microscope. It facilitates histological evaluation of disease-specific morphological alterations. Thereby, it aids in disease diagnosis, prognosis, and assessment of treatment compliance/response. Indeed, with the advent of non-invasive methods, liver biopsy is used less frequently than before, but it is still considered as a gold standard for staging and grading several CLDs. This short review revisits liver biopsy. It highlights the significance of liver biopsy in evaluating CLDs and explains the commonly used Ishak, METAVIR and Batts-Ludwig scoring systems for grading and staging CLDs. The utility of liver biopsy in examining alcohol-related liver disease and non-alcoholic fatty liver disease (NAFLD) is discussed along with the disease-specific alcoholic hepatitis histology score (AHHS) and non-alcoholic fatty liver disease activity score (NAS). Additionally, the review elaborates on the role of liver biopsy in evaluating viral hepatitis, haemochromatosis, and hepatocellular carcinoma. Contextual explanation on the diagnosis of metabolic dysfunction-associated liver disease (MAFLD) is provided. The significance and clinical indications of repeat biopsy are also explained. Lastly, caveats and limitations associated with liver biopsy are reviewed. Essentially, this review collates the application of liver biopsy in assessing various CLDs and provides succinct explanations of the core scoring systems, all under one roof. It is clinically relevant and provides a useful synopsis to budding scientists and hepato-pathologists.

Nivolumab-induced liver injury with a steroid-refractory increase in biliary enzymes, in a patient with malignant mesothelioma: An autopsy case report

This is the first autopsy report of hepatotoxicity from nivolumab immunotherapy for malignant mesothelioma. The increase in levels of biliary enzymes and randomly distributed endothelial damage were steroid-refractory, but second-line option was abandoned because of cachexia. Further discussions are needed regarding the customized management of immune-related toxicities.

PK/PD Modeling of the PDE7 Inhibitor-GRMS-55 in a Mouse Model of Autoimmune Hepatitis

This study aimed to assess the efficacy and explore the mechanisms of action of a potent phosphodiesterase (PDE)7A and a moderate PDE4B inhibitor GRMS-55 in a mouse model of autoimmune hepatitis (AIH). The concentrations of GRMS-55 and relevant biomarkers were measured in the serum of BALB/c mice with concanavalin A (ConA)-induced hepatitis administered with GRMS-55 at two dose levels. A semi-mechanistic PK/PD/disease progression model describing the time courses of measured biomarkers was developed. The emetogenicity as a potential side effect of the studied compound was evaluated in the α₂-adrenoceptor agonist-induced anesthesia model. The results indicate that liver damage observed in mice challenged with ConA was mainly mediated by TNF-α and IFN-γ. GRMS-55 decreased the levels of pro-inflammatory mediators and the transaminase activities in the serum of mice with AIH. The anti-inflammatory properties of GRMS-55, resulting mainly from PDE7A inhibition, led to a high hepatoprotective activity in mice with AIH, which was mediated by an inhibition of pro-inflammatory signaling. GRMS-55 did not induce the emetic-like behavior. The developed PK/PD/disease progression model may be used in future studies to assess the potency and explore the mechanisms of action of new investigational compounds for the treatment of AIH.