Skeletal muscle is a major organ of insulin-induced glucose metabolism. In addition, loss of muscle mass is closely linked to insulin resistance (IR) and metabolic syndrome (Met-S). Skeletal muscle ...loss and accumulation of intramuscular fat are associated with a variety of pathologies through a combination of factors, including oxidative stress, inflammatory cytokines, mitochondrial dysfunction, IR, and inactivity. Sarcopenia, defined by a loss of muscle mass and a decline in muscle quality and muscle function, is common in the elderly and is also often seen in patients with acute or chronic muscle-wasting diseases. The relationship between Met-S and sarcopenia has been attracting a great deal of attention these days. Persistent inflammation, fat deposition, and IR are thought to play a complex role in the association between Met-S and sarcopenia. Met-S and sarcopenia adversely affect QOL and contribute to increased frailty, weakness, dependence, and morbidity and mortality. Patients with Met-S and sarcopenia at the same time have a higher risk of several adverse health events than those with either Met-S or sarcopenia. Met-S can also be associated with sarcopenic obesity. In this review, the relationship between Met-S and sarcopenia will be outlined from the viewpoints of molecular mechanism and clinical impact.
The term “cachexia” is derived from the Greek words kakos (bad) and hexis (habit). Cachexia is a malnutrition associated with chronic diseases such as cancer, chronic heart failure, chronic renal ...failure, and autoimmune diseases, and is characterized by decreased skeletal muscle mass. Cancer cachexia is quite common in patients with advanced cancer. Weight loss is also a characteristic symptom of cancer cachexia, along with decreased skeletal muscle mass. As nutritional supplementation alone cannot improve cachexia, cytokines and tumor-derived substances have been attracting attention as its relevant factors. Cancer cachexia can be also associated with reduced chemotherapeutic effects, increased side effects and treatment interruptions, and even poorer survival. In 2011, a consensus definition of cachexia has been proposed, and the number of relevant research reports has increased significantly. However, the pathogenesis of cachexia is not fully understood, and there are currently few regulatory-approved standard treatments for cachexia. The main reason for this is that multiple etiologies are involved in the development of cachexia. In this review, we will outline the current status of cachexia, the mechanisms of which have been elucidated in recent years, especially from the perspective of advanced cancer.
Aging causes skeletal muscle atrophy, and myofiber loss can be a critical component of this process. In 1989, Rosenberg emphasized the importance of the loss of skeletal muscle mass that occurs with ...aging and coined the term 'sarcopenia'. Since then, sarcopenia has attracted considerable attention due to the aging population in developed countries. The presence of sarcopenia is closely related to staggering, falls and even frailty in the elderly, which in turn leads to the need for nursing care. Sarcopenia is often associated with a poor prognosis in the elderly. Therefore, it is crucial to investigate the causes and pathogenesis of sarcopenia, and to develop and introduce interventional strategies in line with these causes and pathogenesis. Sarcopenia can be a primary component of physical frailty. The association between sarcopenia, frailty and locomotive syndrome is complex; however, sarcopenia is a muscle‑specific concept that is relatively easy to approach in research. In the elderly, a lack of exercise, malnutrition and hormonal changes lead to neuromuscular junction insufficiency, impaired capillary blood flow, reduced repair and regeneration capacity due to a decrease in the number of muscle satellite cells, the infiltration of inflammatory cells and oxidative stress, resulting in muscle protein degradation exceeding synthesis. In addition, mitochondrial dysfunction causes metabolic abnormalities, such as insulin resistance, which may lead to quantitative and qualitative abnormalities in skeletal muscle, resulting in sarcopenia. The present review article focuses on age‑related primary sarcopenia and outlines its pathogenesis and mechanisms.
Body Composition in Chronic Liver Disease Nishikawa, Hiroki; Kim, Soo Ki; Asai, Akira
International journal of molecular sciences,
01/2024, Letnik:
25, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Body composition has recently been attracting people's attention, not only from a cosmetic standpoint but also from the perspective of health and longevity. The body is classified into three ...components: fat, bone, and lean soft tissue, and it is common to see an increase in body fat and a decrease in total body muscle mass with aging. Aging-related loss of muscle mass and muscle function is referred to as primary sarcopenia, while sarcopenia caused by disease-specific conditions is referred to as secondary sarcopenia. On the other hand, the liver-muscle axis has been attracting attention in recent years, and it has become clear that the liver and the skeletal muscles interact with each other. In particular, patients with cirrhosis are prone to secondary sarcopenia due to protein-energy malnutrition, which is a characteristic pathophysiology of the disease, suggesting the importance of the organ-organ network. In this review, we would like to outline the latest findings in this field, with a focus on body composition in liver diseases such as liver cirrhosis, fatty liver disease, alcoholic liver disease, and hepatocellular carcinoma.
Type 2 diabetes (T2D) is a polygenic disease and studies to understand the etiology of the disease have required selectively bred animal models with polygenic background. In this review, we present ...two models; the Goto-Kakizaki (GK) rat and the Oikawa-Nagao Diabetes-Prone (ON-DP) and Diabetes-Resistant (ON-DR) mouse. The GK rat was developed by continuous selective breeding for glucose tolerance from the outbred Wistar rat around 50 years ago. The main cause of spontaneous hyperglycemia in this model is insulin secretion deficiency from pancreatic β-cells and mild insulin resistance in insulin target organs. A disadvantage of the GK rat is that environmental factors have not been considered in the selective breeding. Hence, the GK rat may not be suitable for elucidating predisposition to diabetes under certain environmental conditions, such as a high-fat diet. Therefore, we recently established two mouse lines with different susceptibilities to diet-induced diabetes, which are prone and resistant to the development of diabetes, designated as the ON-DP and ON-DR mouse, respectively. The two ON mouse lines were established by continuous selective breeding for inferior and superior glucose tolerance after high-fat diet feeding in hybrid mice of three inbred strains. Studies of phenotypic differences between ON-DP and ON-DR mice and their underlying molecular mechanisms will shed light on predisposing factors for the development of T2D in the modern obesogenic environment. This review summarizes the background and the phenotypic differences and similarities of GK rats and ON mice and highlights the advantages of using selectively bred rodent models in diabetes research.
Aims/hypothesis
Obesity caused by overeating plays a pivotal role in the development of type 2 diabetes. However, it remains poorly understood how individual meal size differences are determined ...before the development of obesity. Here, we investigated the underlying mechanisms in determining spontaneous food intake in newly established Oikawa–Nagao Diabetes-Prone (ON-DP) and Diabetes-Resistant (ON-DR) mice.
Methods
Food intake and metabolic phenotypes of ON-DP and ON-DR mice under high-fat-diet feeding were compared from 5 weeks to 10 weeks of age. Differences in leptin status at 5 weeks of age were assessed between the two mouse lines. Adipose tissue explant culture was also performed to evaluate leptin production capacity in vitro.
Results
ON-DP mice showed spontaneous overfeeding compared with ON-DR mice. Excessive body weight gain and fat accumulation in ON-DP mice were completely suppressed to the levels seen in ON-DR mice by pair-feeding with ON-DR mice. Deterioration of glucose tolerance in ON-DP mice was also ameliorated under the pair-feeding conditions. While no differences were seen in body weight and adipose tissue mass when comparing the two mouse lines at 5 weeks of age, the ON-DP mice had lower plasma leptin concentrations and adipose tissue leptin gene expression levels. In accordance with peripheral leptin status, ON-DP mice displayed lower anorexigenic leptin signalling in the hypothalamic arcuate nucleus when compared with ON-DR mice without apparent leptin resistance. Explant culture studies revealed that ON-DP mice had lower leptin production capacity in adipose tissue. ON-DP mice also displayed higher DNA methylation levels in the leptin gene promoter region of adipocytes when compared with ON-DR mice.
Conclusions/interpretation
The results suggest that heritable lower leptin production capacity plays a critical role in overfeeding-induced obesity and subsequent deterioration of glucose tolerance in ON-DP mice. Leptin production capacity in adipocytes, especially before the development of obesity, may have diagnostic potential for predicting individual risk of obesity caused by overeating and future onset of type 2 diabetes.
Graphical abstract
Anti-programmed cell death-1 (PD-1) antibodies has been approved to treat HCC. Some PD-1 ligands (PD-L1 and PD-L2) negative tumors respond to treatment of anti-PD-1 antibodies, and this fact may be ...caused by the expression of PD-1 ligands on non-tumor cells. PD-L1 was recently found to be expressed on CD14
cells from cancer patients. We investigate PD-1 ligands expression on CD14
cells of patients with HCC and the role of CD14
cells in an antitumor response. In this study, 87 patients diagnosed with HCC were enrolled. CD14
cells from patients with HCC expressed PD-L1 (4.5-95.5%) and PD-L2 (0.2-95.0%). According to cut-off values, we classified patients as those either with PD-L1
PD-L2
CD14
cells or other types of CD14
cells. The overall survival of patients with PD-L1
PD-L2
CD14
cells was shorter than that of patients with other types of CD14
cells (p = 0.0023). PD-L1
PD-L2
CD14
cells produced IL-10 and CCL1, and showed little tumoricidal activity against HepG2 cells. The tumoricidal activity of CD8
cells from patients with PD-L1
PD-L2
CD14
cells were suppressed by co-cultivation with CD14
cells from the syngeneic patient. Furthermore, anti-PD-1 antibody restored their tumoricidal activity of CD8
cells. In conclusion, some patients with HCC have PD-L1
PD-L2
CD14
cells that suppress their antitumor response. These inhibitory functions of CD14
cells may be associated with a poor prognosis in these patients.
Zinc is an essential trace element for the maintenance of life because it acts as a center of activity or cofactor for hundreds of enzymes. Zinc deficiency causes a variety of symptoms, including ...anemia, dermatitis, stomatitis, alopecia, bedsores, decreased appetite, impaired growth, gonadal dysfunction, susceptibility to infection, and taste disorders, etc. In March 2017, zinc acetate hydrate, which had been approved for Wilson disease in Japan, received an additional indication for hypozincemia. Hypozincemia is frequently observed in patients with chronic liver disease (CLD), especially cirrhosis, and it has recently been shown that hypozincemia is closely related to the development of liver fibrosis and increased risk of liver carcinogenesis, in addition to the appearance of various subjective symptoms. Moreover, hypozincemia in CLD may be associated with sarcopenia (i.e., decrease in muscle strength and muscle mass) and frailty (i.e., vulnerability), which receive much attention these days. It is assumed that treatment with zinc acetate hydrate will become widespread in patients with CLD. Zinc acetate hydrate may also have potential for improving sarcopenia in patients with CLD. This review primarily outlines the significance of zinc in patients with CLD.
Signal transducer and activator of transcription 3 (STAT3) is a latent transcription factor that contributes to tumor cell growth and survival and is often constitutively active in several types of ...cancers, which makes it an attractive target for cancer therapy. We identified 5,5′-(pentane-1,5′-diyl)bis(2-methyl-1,4-benzoquinone) (BPMB) as a new STAT3 inhibitor. BPMB inhibited the transcriptional activities of STAT3, despite its inability to reduce the phosphorylation and nuclear translocation of STAT3. BPMB selectively inhibited the proliferation of human breast cancer cell lines with constitutively activated STAT3. Furthermore, a gel retardation pattern was obtained by immunoblotting only when those STAT3-activated cell lines were treated with BPMB. The shifted bands could be immunoblotted with anti-STAT3 antibody but not with anti-STAT1/STAT5 antibody, and were stable under reducing conditions. The purified recombinant STAT3 protein treated with BPMB afforded a similar band shift pattern. Matrix-assisted laser desorption/ionization-mass spectrometry analysis of the component comprising the main shifted band suggested that the complex is a STAT3 homodimer crosslinked by BPMB through a Michael addition with Cys550 in the linker domain. Alanine replacement at this position resulted in reduction of the STAT3 dimer formation in the gel retardation assay. Thus, our results suggest that BPMB inhibits the proliferation of STAT3-activated cell lines, presumably through acylation of the linker domain and subsequent induction of the inactive STAT3 complexes.
Signal transducer and activator of transcription 3 (STAT3) plays a critical role in regulating cell growth, survival, and metastasis. STAT3 signaling is constitutively activated in various types of ...hematologic or solid malignancies. YHO-1701 has been developed as an orally available STAT3 inhibitor. Herein, YHO-1701 in combination with molecular-targeted agents was evaluated. Additive or synergistic effects were observed in a broad spectrum of "combination treatment + cell line" pairs. Of particular interest was the synergistic effect observed when YHO-1701 was combined with imatinib or dasatinib breakpoint cluster region-abelson (BCR-ABL) inhibitors, osimertinib epidermal growth factor receptor (EGFR) inhibitor, crizotinib, alectinib, or ceritinib anaplastic lymphoma kinase (ALK) inhibitors. The results further showed a close relationship between these synergistic effects and the cellular levels of the key molecules involved in the target pathways for YHO-1701 and each combination drug. The combination of YHO-1701 with alectinib resulted in significantly greater antitumor activity without exhibiting body weight loss in an NCI-H2228 echinoderm microtubule-associated protein-like 4 (EML4)-ALK fusion xenograft mouse model. Our results strongly suggest that the logical strategy in combination with the novel STAT3 inhibitor YHO-1701 and other mechanistically different targeted agents, could be a promising approach in future clinical settings.
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