Chronic hyperlipidemia and/ or hyperglycemia can impair various organs, such as the liver, kidney, and pancreas, through metabolic abnormalities. Metabolic dysfunction-associated steatohepatitis (MASH), related from nonalcoholic steatohepatitis (NASH), exhibits complex pathophysiological features, and animal models of MASH are essential for elucidating its underlying mechanisms. This study aimed to induce MASH-like lesions in obese type 2 diabetic mice by feeding them a high-fat/high-sucrose/high-cholesterol (HFSC) diet. C57BL/6J, db/db, and KK-Ay mice at 6 weeks of age were fed an HFSC diet for 8 weeks. Collected samples were subjected to hematobiochemical, gene expression, and histopathological analyses. At 14 weeks of age, both diabetic mouse models showed hyperglycemia and hyperlipidemia, with hypercholesterolemia observed in HFSC-fed groups. HFSC-fed db/db and KK-Ay mice showed increased hepatic steatosis, and KK-Ay mice also showed partial hepatic fibrosis in pericentral venous and perivascular areas. mRNA analysis revealed upregulation of hepatic genes involved in lipid synthesis, inflammation, and fibrosis in diabetic mice fed the HFSC diet. Obese type 2 diabetic mice fed a high-fat/high-sucrose/high-cholesterol diet showed early indications of MASH-like lesions, supporting their utility as MASH animal models.

Cisplatin is a widely used platinum-based chemotherapeutic agent whose dose-limiting toxicities, including nephrotoxicity, neurotoxicity, and myelosuppression, have been extensively characterized. In contrast, skeletal muscle has not traditionally been regarded as a primary target of cisplatin toxicity. However, accumulating experimental evidence indicates that cisplatin administration leads to a significant reduction in skeletal muscle mass and fiber size, even in the absence of tumor burden or overt cachexia. These findings suggest that cisplatin itself can directly induce skeletal muscle atrophy as a form of drug-induced toxicity. Animal and cell-based studies have demonstrated that cisplatin activates catabolic signaling in skeletal muscle, most notably through enhanced protein degradation via the ubiquitin–proteasome system. This response is accompanied by increased expression of muscle-specific E3 ubiquitin ligases, including muscle RING finger 1 (MuRF1) and muscle atrophy F-box protein (MAFbx/atrogin-1), which are established mediators of skeletal muscle atrophy. In parallel, suppression of anabolic signaling, particularly impairment of the insulin-like growth factor-1/Akt/mechanistic target of rapamycin complex 1 (mTORC1) pathway, has been reported, indicating a shift in muscle protein turnover toward a catabolic state. Recent studies suggest that cellular stress responses, such as endoplasmic reticulum stress, may be involved in regulating these processes. This review summarizes experimental evidence supporting cisplatin-induced skeletal muscle atrophy and discusses the underlying toxicological processes from a muscle-centered perspective. By distinguishing drug-induced muscle toxicity from cancer cachexia and other wasting conditions, we propose that skeletal muscle should be recognized as a clinically relevant but underestimated target organ of cisplatin toxicity. Improved understanding of these processes may support the development of strategies to preserve muscle mass and function during cancer chemotherapy.

Multiple chemical sensitivity (MCS) is characterized by neuropsychological symptoms including anxiety, depression, and fatigue following exposure to environmental chemicals, yet its underlying mechanisms remain poorly understood. Linalool, a monoterpene alcohol widely used in consumer products, has been suggested as a potential contributor to MCS. To elucidate its neural effects, we examined the behavioral effects of linalool inhalation in mice. Linalool exposure induced both anxiety- and depression-like behaviors. While the depression-like behavior required olfactory input, the anxiety-like behavior occurred independently of olfactory perception. Our previous studies demonstrated that inhaled linalool accumulates in the brain and undergoes cytochrome P450 (P450)-dependent metabolism. We therefore tested whether P450-mediated metabolism contributes to the behavioral effects of linalool. Significantly, inhibition of P450 activity abolished the anxiety-like behavior. These findings reveal an olfactory-independent mechanism by which inhaled linalool induces anxiety-like behavior in mice and suggest that P450 activity is required for this effect, providing a basis for investigating fragrance-induced MCS-like neurobehavioral responses.