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Abstract Lipodystrophy and obesity are associated with insulin resistance and metabolic syndrome accompanied by fat tissue dysregulation. Here, we show that serine protease inhibitor A1 (SerpinA1) expression in the liver is increased during recovery from lipodystrophy caused by the adipocyte-specific loss of insulin signaling in mice. SerpinA1 induces the proliferation of white and brown preadipocytes and increases the expression of uncoupling protein 1 (UCP1) to promote mitochondrial activation in mature white and brown adipocytes. Liver-specific SerpinA1 transgenic mice exhibit increased browning of adipose tissues, leading to increased energy expenditure, reduced adiposity and improved glucose tolerance. Conversely, SerpinA1 knockout mice exhibit decreased adipocyte mitochondrial function, impaired thermogenesis, obesity, and systemic insulin resistance. SerpinA1 forms a complex with the Eph receptor B2 and regulates its downstream signaling in adipocytes. These results demonstrate that SerpinA1 is an important hepatokine that improves obesity, energy expenditure and glucose metabolism by promoting preadipocyte proliferation and activating mitochondrial UCP1 expression in adipocytes.

Abstract In in situ capturing-based spatial transcriptomics, spots of the same size and printed at fixed locations cannot precisely capture the randomly-located single cells, therefore inherently failing to profile transcriptome at the single-cell level. To this end, we present STIE, an Expectation Maximization algorithm that aligns the spatial transcriptome to its matched histology image-based nuclear morphology and recovers missing cells from ~70% gap area, thereby achieving the real single-cell level and whole-slide scale deconvolution, convolution, and clustering for both low- and high-resolution spots. STIE characterizes cell-type-specific gene expression and demonstrates outperforming concordance with true cell-type-specific transcriptomic signatures than the other spot- and subspot-level methods. Furthermore, STIE reveals the single-cell level insights, for instance, lower actual spot resolution than its reported spot size, unbiased evaluation of cell type colocalization, superior power of high-resolution spot in distinguishing nuanced cell types, and spatial cell-cell interactions at the single-cell level other than spot level.

ABSTRACT The potential liability to hypercatabolism in lipodystrophy remains to be fully elucidated. Here we report a 28‐year‐old Japanese woman with acquired generalized lipodystrophy, who presented with recurrence of panniculitis and anemia. After corticosteroid treatment was started, she showed rapid reductions in body weight and lean mass by 15% at maximum, accompanied by an elevated urea nitrogen/creatinine ratio, which recovered almost fully as the corticosteroid treatment was tapered and discontinued. She had multiple risk factors for hypercatabolism: lack of metabolic reserves, insulin resistance, and hyperglycemia due to lipodystrophy, lowered daily activity due to anemia, persistent inflammation, and wasting associated with panniculitis, and relatively insufficient energy and protein intake during hospitalization. More attention should be paid to the potential liability to hypercatabolism in patients with lipodystrophy, and to skeletal muscle loss as an adverse effect of corticosteroid treatment in patients at high risk, such as those with diabetes or decreased metabolic reserves.

Abstract Immune checkpoint inhibitors targeting PD-1/L1 have modest efficacy in hepatocellular carcinoma as single agents. Targeting membranous phosphatidylserine may induce pro-inflammatory and -immune stimulating effects that enhance immunotherapy activity. This hypothesis was tested in a single-arm phase 2 trial evaluating frontline bavituximab, a phosphatidylserine targeting antibody, plus pembrolizumab (anti-PD-1) in patients with unresectable hepatocellular carcinoma (NCT03519997). The primary endpoint was investigator-assessed objective response rate among evaluable patients, and secondary end points included progression-free survival, incidence of adverse events, overall survival, and duration of response. Among 28 evaluable patients, the confirmed response rate was 32.1%, which met the pre-specified endpoint, and the median progression-free survival was 6.3 months (95% CI, 1.3–11.3 months). Treatment related-adverse events of any grade occurred in 45.7% of patients, with grade 3 or greater adverse events in 14.3% of patients. Adverse events of any cause were observed in 33 patients (94.3%), with grade 3 or greater adverse events in 11 patients (31.4%). Prespecified exploratory analyses of baseline tumor specimens showed that a depletion of B cells, and the presence of fibrotic tissue and expression of immune checkpoints in stroma was associated with tumor response. These results suggest that targeting phosphatidylserine may lead to synergistic effects with PD-1 blockade without increasing toxicity rates, and future studies on this therapeutic strategy may be guided by biomarkers characterizing the pre-treatment tumor microenvironment.

Background and Aims: Effective approaches for prevention of hepatocellular carcinoma (HCC) will have a significant impact on HCC-related mortality. There are strong preclinical data and rationale to support targeting epidermal growth factor receptor (EGFR) for HCC chemoprevention. Small molecule inhibitors of EGFR have been Food and Drug Administration–approved for cancer therapy, which provides an opportunity to repurpose one of these drugs for chemoprevention of HCC. Unfortunately, the frequency of side effects associated with administration of these drugs at oncology doses renders them ineffective for chemoprevention. This clinical trial assesses whether lower doses of one of these inhibitors, erlotinib, still engages EGFR in the liver to block signaling (eg, EGFR phosphorylation). The objective of this clinical trial was determination of a safe and minimum effective dose of erlorinib for which ≥ 50% reduction phospho-EGFR immunohistochemical staining in the liver was observed. Methods: Forty six participants were preregistered and 25 participants were registered in this multicenter trial. By dose de-escalation trial design, cohorts of participants received a 7-day course of erlotinib 75 mg/day, 50 mg/day or 25 mg/day with liver tissue acquisition prior to and after erlotinib. Results: A ≥50% reduction phospho-EGFR immunohistochemical staining in the liver was observed in a minimum of 40% of participants (predetermined threshhold) at each of the dose levels. Erlotinib was very well tolerated with few side effects observed, particularly at the dose of 25 mg/day. Favorable modulation of the Prognostic Liver Signature was observed in participants who received erlotinib. Conclusion: These data support the selection of erlotinib doses as low as 25 mg/day of for a longer intervention to assess for evidence of efficacy as an HCC chemoprevention drug (ClinicalTrials.gov NCT02273362).

Abstract Diabetes is known to increase the risk of nonalcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC). Here we treat male STAM (STelic Animal Model) mice, which develop diabetes, NASH and HCC associated with dysbiosis upon low-dose streptozotocin and high-fat diet (HFD), with insulin or phlorizin. Although both treatments ameliorate hyperglycemia and NASH, insulin treatment alone lead to suppression of HCC accompanied by improvement of dysbiosis and restoration of antimicrobial peptide production. There are some similarities in changes of microflora from insulin-treated patients comorbid with diabetes and NASH. Insulin treatment, however, fails to suppress HCC in the male STAM mice lacking insulin receptor specifically in intestinal epithelial cells (ieIRKO), which show dysbiosis and impaired gut barrier function. Furthermore, male ieIRKO mice are prone to develop HCC merely on HFD. These data suggest that impaired gut insulin signaling increases the risk of HCC, which can be countered by restoration of insulin action in diabetes.

ABSTRACT Aim To investigate the impact of the COVID‐19 pandemic and its preventive measures on the glycemic and lipid control in people with diabetes mellitus (DM). Materials and methods We conducted this retrospective cohort study from April 2019 to March 2021; we termed the period from April 2019 to March 2020 as the pre‐COVID‐19 period, and the period from April 2020 to March 2021 as the COVID‐19 period, and divided each of these two periods into four quarters. Results In the 1st quarter of the COVID period, when the Japanese government declared the first public health emergency, 3,465 people with diabetes mellitus were receiving treatment, which was 10.4% lower than that in the pre‐COVID period. The annual mean HbA1c level was significantly elevated in the COVID‐19 period. The annual mean total cholesterol (TC) and triglyceride (TG) levels were also significantly higher in the COVID‐19 period. Although there were no significant differences in the glycemic control or annual medication between the two periods in people with type 1 diabetes mellitus, the annual mean HbA1c, TC, and TG levels were significantly higher in the COVID‐19 period in people with type 2 diabetes mellitus. Furthermore, a significant increase in the percentage of prescriptions for glinides, biguanides, sodium‐glucose cotransporter 2 inhibitors, and glucagon‐like peptide‐1 receptor agonists for people with type 2 diabetes mellitus was observed in the COVID period. Conclusions It appears from our study that COVID‐19 and its preventive measures had a negative impact on the glycemic and lipid control in people with diabetes mellitus.

ABSTRACT Aims/Introduction Patients with type 2 diabetes mellitus are reported to be at a high risk for sarcopenia, and are known to have a poorer sleep quality. However, the association between sleep quality and skeletal muscle in patients with type 2 diabetes mellitus is not yet precisely understood. Materials and Methods A total of 110 inpatients with type 2 diabetes mellitus aged 40–90 years were enrolled. The sleep quality was assessed using the Pittsburgh sleep quality index (PSQI). Skeletal muscle mass was measured using bioelectrical impedance analysis. Muscle strength was evaluated by measuring the grip strength. We also performed dietary surveys and measurements of the plasma amino acid levels. Results A high total score on the PSQI was significantly associated with reduced muscle strength, and the association persisted even after adjustments for confounders. On the other hand, adjusted analysis did not reveal any significant associations between the PSQI total score and the skeletal muscle mass. In regard to the associations with subscores of the PSQI, the scores for sleep latency, sleep efficiency, and daytime dysfunction were significantly negatively associated with the muscle strength. Although poor sleep quality was associated with a high confectionery intake and low plasma arginine, citrulline, and ornithine levels, neither confectionery intake levels nor the plasma levels of these amino acids was associated with the muscle strength. Conclusions Our study revealed a significant association between the sleep quality and muscle strength in patients with type 2 diabetes mellitus. These results suggest that poor sleep quality is an important risk factor for sarcopenia in patients with type 2 diabetes mellitus.

ABSTRACT Aims/Introduction To evaluate the impact of the COVID‐19 pandemic on the glycemic control, eating habits, and body composition of people with diabetes mellitus; to identify the determinants of worsening glycemic control in people with diabetes mellitus. Materials and methods This retrospective, longitudinal observational study was performed in outpatients with diabetes mellitus who visited our hospital between April 2019 and March 2020 (pre‐COVID‐19 period) and continued for follow up from April 2020 to March 2021 (COVID‐19 period). We compared the glycemic control, nutritional intakes, and body composition of people with diabetes mellitus between the two periods. The changes in the HbA1c values (ΔHbA1c) and other study variables were compared between the two periods. Logistic regression analysis was performed to identify the factors associated with the increase of HbA1c levels. Results A significant increase of HbA1c was observed during the COVID‐19 period. The percent fat mass (FM) also increased, while the percent skeletal muscle mass (SMM) decreased during the COVID‐19 period. After adjustments for age and sex, the ΔBMI (OR:2.33), ΔFM (OR:1.45), and ΔSMM (OR:0.51) were identified as being associated with elevated levels of HbA1c. Conclusions The COVID‐19 pandemic had a negative impact on the glycemic control and body composition of people with diabetes mellitus. The increased body weight and FM and decreased SMM observed during the pandemic were associated with poor glycemic control in people with diabetes mellitus.

Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes are interacting comorbidities of obesity, and increased hepatic de novo lipogenesis (DNL), driven by hyperinsulinemia and carbohydrate overload, contributes to their pathogenesis. Fatty acid synthase (FASN), a key enzyme of hepatic DNL, is upregulated in association with insulin resistance. However, the therapeutic potential of targeting FASN in hepatocytes for obesity-associated metabolic diseases is unknown. Here, we show that hepatic FASN deficiency differentially affects NAFLD and diabetes depending on the etiology of obesity. Hepatocyte-specific ablation of FASN ameliorated NAFLD and diabetes in melanocortin 4 receptor–deficient mice but not in mice with diet-induced obesity. In leptin-deficient mice, FASN ablation alleviated hepatic steatosis and improved glucose tolerance but exacerbated fed hyperglycemia and liver dysfunction. The beneficial effects of hepatic FASN deficiency on NAFLD and glucose metabolism were associated with suppression of DNL and attenuation of gluconeogenesis and fatty acid oxidation, respectively. The exacerbation of fed hyperglycemia by FASN ablation in leptin-deficient mice appeared attributable to impairment of hepatic glucose uptake triggered by glycogen accumulation and citrate-mediated inhibition of glycolysis. Further investigation of the therapeutic potential of hepatic FASN inhibition for NAFLD and diabetes in humans should thus consider the etiology of obesity.

Abstract The limited performance of guideline‐recommended abdominal ultrasound and serum alpha‐fetoprotein (AFP) highlights the urgent, unmet need for new biomarkers for more accurate detection of early hepatocellular carcinoma (HCC). To this end, we have conducted a prospective clinical validation study to evaluate the performance of the HelioLiver Test, a multi‐analyte blood test combining cell‐free DNA methylation patterns, clinical variables, and protein tumor markers. A blinded, multicenter validation study was performed with 247 subjects, including 122 subjects with HCC and 125 control subjects with chronic liver disease. The performance of the HelioLiver Test was compared with AFP and the GALAD score as established HCC surveillance blood tests. The performance of the HelioLiver Test (area under the receiver operating characteristic curve [AUROC] = 0.944) was superior to both AFP (AUROC = 0.851; p < 0.0001) and GALAD (AUROC = 0.899; p < 0.0001). Using a prespecified diagnostic algorithm, the HelioLiver Test showed sensitivities of 85% (95% confidence interval [CI], 78%–90%) for HCC of any stage and 76% (95% CI, 60%–87%) for early stage (American Joint Committee on Cancer [AJCC] I and II) HCC. In contrast, AFP (≥20 ng/mL) alone and the GALAD score (≥−0.63) showed lower sensitivities of 62% (95% CI, 54%–70%) and 75% (95% CI, 67%‐82%) for HCC overall, and 57% (95% CI, 40%–71%) and 65% (95% CI, 49%–79%) for early stage (AJCC I and II) HCC, respectively. The specificities of the HelioLiver Test (91%; 95% CI, 85%–95%), AFP (97%; 95% CI, 92%–99%), and the GALAD score (94%; 95% CI, 88%–97%) were similar for control subjects. The HelioLiver Test showed superior performance for HCC detection compared to with both AFP and the GALAD score and warrants further evaluation in HCC surveillance settings.

Little is known about the epigenetic mechanisms of the first cell fate commitment in humans. Here, the authors show that activation of the miRNA cluster C19MC confers differentiation potential into trophoblast lineages on human embryonic stem cells.

Abstract Gamma‐synuclein (SNCG) promotes invasive behavior and is reportedly a prognostic factor in a range of cancers. However, its role in biliary tract carcinoma (BTC) remains unknown. Consequently, we investigated the clinicopathological significance and function of SNCG in BTC. Using resected BTC specimens from 147 patients with adenocarcinoma (extrahepatic cholangiocarcinoma [ECC, n = 96]; intrahepatic cholangiocarcinoma [ICC, n = 51]), we immunohistochemically evaluated SNCG expression and investigated its correlation with clinicopathological factors and outcomes. Furthermore, cell lines with high SNCG expression were selected from 16 BTC cell lines and these underwent cell proliferation and migration assays by siRNAs. In the results, SNCG expression was present in 22 of 96 (22.9%) ECC patients and in 10 of 51 (19.6%) ICC patients. SNCG expression was significantly correlated with poorly differentiated tumor in both ECC and ICC (p = 0.01 and 0.03, respectively) and with perineural invasion and lymph node metastases in ECC (p = 0.04 and 0.003, respectively). Multivariate analyses revealed that SNCG expression was an independent poor prognostic factor in both OS and RFS in both ECC and ICC. In vitro analyses showed high SNCG expression in three BTC cell lines (NCC‐BD1, NCC‐BD3, and NCC‐CC6‐1). Functional analysis revealed that SNCG silencing could suppress cell migration in NCC‐BD1 and NCC‐CC6‐1 and downregulate cell proliferation in NCC‐CC6‐1 significantly. In conclusion, SNCG may promote tumor cell activity and is potentially a novel prognostic marker in BTC.

Furuzono et al. identify DS20060511, a skeletal muscle cell-specific GLUT4 translocation enhancer. They find that DS20060511 have remarkable effects on lowering blood glucose and enhancing skeletal muscle glucose uptake via GLUT4, highlighting its potential as antidiabetic medicine.

Genomic variations are associated with gene expression levels, which are called expression quantitative trait loci (eQTL). Most eQTL may affect the total gene expression levels by regulating transcriptional activities of a specific promoter. However, the direct exploration of genomic loci associated with promoter activities using RNA-seq data has been challenging because eQTL analyses treat the total expression levels estimated by summing those of all isoforms transcribed from distinct promoters. Here we propose a new method for identifying genomic loci associated with promoter activities, called promoter usage quantitative trait loci (puQTL), using conventional RNA-seq data. By leveraging public RNA-seq datasets from the lymphoblastoid cell lines of 438 individuals from the GEUVADIS project, we obtained promoter activity estimates and mapped 2,592 puQTL at the 10% FDR level. The results of puQTL mapping enabled us to interpret the manner in which genomic variations regulate gene expression. We found that 310 puQTL genes (16.1%) were not detected by eQTL analysis, suggesting that our pipeline can identify novel variant-gene associations. Furthermore, we identified genomic loci associated with the activity of "hidden" promoters, which the standard eQTL studies have ignored. We found that most puQTL signals were concordant with at least one genome-wide association study (GWAS) signal, enabling novel interpretations of the molecular mechanisms of complex traits. Our results emphasize the importance of the re-analysis of public RNA-seq datasets to obtain novel insights into gene regulation by genomic variations and their contributions to complex traits.

Abstract Epidemiological and animal studies have revealed that sodium‐glucose cotransporter 2 (SGLT2) inhibitors suppress cardiovascular events in subjects with type 2 diabetes and atherosclerosis in animal models of diabetes. However, it still remains unclear if the anti‐atherosclerotic effect of SGLT2 inhibitors is entirely dependent on their glucose‐lowering effect. Tofogliflozin, a highly specific SGLT2 inhibitor, was administrated to apolipoprotein‐E‐deficient (ApoEKO) with streptozotocin (STZ)‐induced diabetes and nondiabetic ApoEKO mice. After 6 weeks, samples were collected to investigate the histological changes and peritoneal macrophage inflammatory cytokine levels. Tofogliflozin suppressed atherosclerosis in the diabetic ApoEKO mice. The atherosclerosis lesion areas and accumulation of macrophages in these areas were reduced by tofogliflozin treatment. The expression levels of interleukin (IL)‐1β and IL‐6 in the peritoneal macrophages were significantly suppressed in the tofogliflozin‐treated diabetic ApoEKO mice. Tofogliflozin treatment failed to inhibit atherosclerosis in the nondiabetic ApoEKO mice. No significant difference in the anti‐atherosclerotic effects of insulin and tofogliflozin was observed between diabetic ApoEKO mice with equivalent degrees of glycemic control achieved with the two treatments. Insulin treatment significantly reduced the IL‐1β and IL‐6 expression levels in the peritoneal macrophages of the diabetic ApoEKO mice. Significant decrease of the LPS‐stimulated IL‐1β concentrations was also observed in the conditioned medium of the peritoneal macrophages collected from insulin‐ and tofogliflozin‐treated diabetic ApoEKO mice. These results suggest that tofogliflozin suppresses atherosclerosis by improving glucose intolerance associated with inhibition of inflammation. Tofogliflozin suppresses atherosclerosis in ApoEKO mice with STZ‐induced diabetes via its glucose‐lowering effect.

Abstract Background Colibactin-producing Escherichia coli containing polyketide synthase (pks + E. coli) has been shown to be involved in colorectal cancer (CRC) development through gut microbiota analysis in animal models. Stool status has been associated with potentially adverse gut microbiome profiles from fecal analysis in adults. We examined the association between stool patterns and the prevalence of pks + E. coli isolated from microbiota in fecal samples of 224 healthy Japanese individuals. Results Stool patterns were determined through factorial analysis using a previously validated questionnaire that included stool frequency, volume, color, shape, and odor. Factor scores were classified into tertiles. The prevalence of pks + E. coli was determined by using specific primers for pks + E. coli in fecal samples. Plasma and fecal fatty acids were measured via gas chromatography-mass spectrometry. The prevalence of pks + E. coli was 26.8%. Three stool patterns identified by factorial analysis accounted for 70.1% of all patterns seen (factor 1: lower frequency, darker color, and harder shape; factor 2: higher volume and softer shape; and factor 3: darker color and stronger odor). Multivariable-adjusted odds ratios (95% confidence intervals) of the prevalence of pks + E. coli for the highest versus the lowest third of the factor 1 score was 3.16 (1.38 to 7.24; P for trend = 0.006). This stool pattern exhibited a significant positive correlation with fecal isobutyrate, isovalerate, valerate, and hexanoate but showed a significant negative correlation with plasma eicosenoic acid and α-linoleic acid, as well as fecal propionate and succinate. No other stool patterns were significant. Conclusions These results suggest that stool patterns may be useful in the evaluation of the presence of tumorigenic bacteria and fecal fatty acids through self-monitoring of stool status without the requirement for specialist technology or skill. Furthermore, it may provide valuable insight about effective strategies for the early discovery of CRC.

Abstract Aims/Introduction To prevent diabetic complications, strict glucose control and frequent monitoring of blood glucose levels with invasive methods are necessary. We considered the monitoring of tear glucose levels might be a possible method for non‐invasive glucose monitoring. To develop tear glucose monitoring for clinical application, we investigated the precise correlation between the blood and tear glucose concentrations. Materials and Methods A total of 10 participants and 20 participants with diabetes were admitted, and blood and tear samples were collected. Before statistical analysis, we eliminated tear samples contaminated with blood. We observed the daily blood and tear glucose dynamics, and carried out a random intercept model analysis to examine the association between the blood and tear glucose concentrations. Results Tear occult blood tests showed that the tear glucose concentrations and their variation increased in both participants with and without diabetes as contamination of blood increased. In both participants with and without diabetes, fluctuations of the plasma glucose concentrations were observed depending on the timing of collection of the samples, and the dynamics of the tear glucose concentrations paralleled those of the plasma glucose concentrations. The random intercept model analysis showed a significant association between the plasma and tear glucose concentrations in participants with diabetes (P

Abstract Background Psoriasis is a chronic inflammatory skin disease, for which genome-wide association studies (GWAS) have identified many genetic variants as risk markers. However, the details of underlying molecular mechanisms, especially which variants are functional, are poorly understood. Methods We utilized a computational approach to survey psoriasis-associated functional variants that might affect protein functions or gene expression levels. We developed a pipeline by integrating publicly available datasets provided by GWAS Catalog, FANTOM5, GTEx, SNP2TFBS, and DeepBlue. To identify functional variants on exons or splice sites, we used a web-based annotation tool in the Ensembl database. To search for noncoding functional variants within promoters or enhancers, we used eQTL data calculated by GTEx. The data of variants lying on transcription factor binding sites provided by SNP2TFBS were used to predict detailed functions of the variants. Results We discovered 22 functional variant candidates, of which 8 were in noncoding regions. We focused on the enhancer variant rs72635708 (T > C) in the 1p36.23 region; this variant is within the enhancer region of the ERRFI1 gene, which regulates lipid metabolism in the liver and skin morphogenesis via EGF signaling. Further analysis showed that the ERRFI1 promoter spatially contacts with the enhancer, despite the 170 kb distance between them. We found that this variant lies on the AP-1 complex binding motif and may modulate binding levels. Conclusions The minor allele rs72635708 (rs72635708-C) might affect the ERRFI1 promoter activity, which results in unstable expression of ERRFI1, enhancing the risk of psoriasis via disruption of lipid metabolism and skin cell proliferation. Our study represents a successful example of predicting molecular pathogenesis by integration and reanalysis of public data.

Insulin signaling has been implicated in the metabolism as well as aging and longevity. Type 2 diabetes mellitus and its core pathology, insulin resistance, has also been implicated in the development of Alzheimer's disease (AD) and amyloid-β deposition in humans. By contrast, genetic ablation of the insulin/IGF-1 signaling (IIS) pathway components, e.g. insulin receptor substrate (IRS)-2, has been documented to suppress amyloid-β accumulation in the brains of transgenic mice overexpressing AD mutant β-amyloid precursor protein (APP). Therefore, the brain IIS may be a key modifiable molecular target in the pathophysiology of AD. IRS-1 and IRS-2 are critical nodes in IIS as substrates for insulin receptor and IGF-1 receptor, although the functional differences between IRS-1 and IRS-2 in the adult brain are yet to be explored. To examine their relative contribution to the brain IIS activity and AD pathomechanism, we generated APP transgenic mice lacking either IRS-1 or IRS-2. IRS-1 deficiency had little effects on the brain IIS pathway associated with compensatory activation of IRS-2, whereas IRS-2 deficiency was not fully compensated by activation of IRS-1, and the downstream activation of Akt also was significantly compromised. Pathological analyses of the cortical tissues showed that the biochemical levels of soluble and insoluble amyloid-β, the amyloid-β histopathology, and tau phosphorylation were not affected by the absence of IRS-1, in contrast to the marked alteration in IRS-2 deleted mice. These results suggest the predominance of IRS-2 in the brain IIS, and support the hypothesis that reduced IIS exerts anti-amyloid effects in the brain.

Abstract Background Based on epidemiological and experimental studies, type 2 diabetes mellitus (T2DM), especially insulin resistance that comprises the core mechanism of T2DM, has been recognized as a significant risk factor for Alzheimer’s disease (AD). Studies in humans and diabetic AD model mice have indicated a correlation between insulin resistance and increased amyloid deposition in the brain. Paradoxically, mice with targeted disruption of genes involved in the insulin signaling pathway showed protective effects against the AD-related pathology. These conflicting observations raise an issue as to the relationship between dysregulation of insulin signaling and AD pathophysiology. Methods To study the causal relations and molecular mechanisms underlying insulin resistance-induced exacerbation of amyloid pathology, we investigated the chronological changes in the development of insulin resistance and amyloid pathology in two independent insulin-resistant AD mouse models, i.e., long-term high-fat diet (HFD) feeding and genetic disruption of Irs2, in combination with dietary interventions. In addition to biochemical and histopathological analyses, we examined the in vivo dynamics of brain amyloid-β (Aβ) and insulin by microdialysis technique. Results HFD-fed diabetic AD model mice displayed a reduced brain response to peripheral insulin stimulation and a decreased brain to plasma ratio of insulin during the hyperinsulinemic clamp. Diet-induced defective insulin action in the brain was accompanied by a decreased clearance of the extracellular Aβ in vivo and an exacerbation of brain amyloid pathology. These noxious effects of the HFD both on insulin sensitivity and on Aβ deposition in brains were reversibly attenuated by dietary interventions. Importantly, HFD feeding accelerated Aβ deposition also in the brains of IRS-2-deficient AD mice. Conclusions Our results suggested a causal and reversible association of brain Aβ metabolism and amyloid pathology by diet-dependent, but not genetically-induced, insulin-resistance. These observations raise the possibility that the causal factors of insulin resistance, e.g., metabolic stress or inflammation induced by HFD feeding, but not impaired insulin signaling per se, might be directly involved in the acceleration of amyloid pathology in the brain.

Endoplasmic reticulum (ER) stress has been proposed to play a role in metabolic diseases. Here, Sasako and colleagues identify stromal cell-derived factor 2 like 1 (Sdf2l1) as a regulator of the ER stress response to feeding in the liver, and suggest that its downregulation may promote diabetes and hepatic steatosis in humans.

BackgroundThe aim of our study was to evaluate the influence of changes of nutritional status and body composition on the results of comprehensive geriatric assessment (CGA) in inpatients of a geriatric ward. Sex differences in these relationships were also investigated.MethodsA total of 212 elderly patients (>65 years old) admitted to the geriatric ward at the University of Tokyo hospital between 2012 and 2019 were enrolled in this study. CGA (ADL, IADL, MMSE, GDS, Vitality Index) was performed, along with assessment of body compositions (appendicular muscle mass, abdominal muscle mass, body fat mass) and blood malnutrition biomarkers (serum albumin, pre-albumin, 25-hydroxy vitamin D, zinc, hemoglobin concentrations).ResultsMultiple linear regression analysis showed that upper, lower limbs and abdominal muscle masses were significantly associated with the score on ADL in men. On the other hand, abdominal muscle mass was negatively associated with the scores on GDS. Body fat mass was also negatively associated with the score on IADL. In contrast, in women, multiple linear regression analysis failed to show any significant associations between body composition parameters and scores on any domains of CGA. Unlike in men, however, blood malnutrition biomarkers were significantly associated with ADL, IADL, MMSE, and Vitality Index in women.ConclusionsOur study findings revealed that the association of the nutritional status and body composition with the functional status in the elderly differs by sex. These results suggest that intensification of exercise in men and improvement of the nutritional status in women are particularly useful to maintain the functional status.

Obesity is associated with low-grade chronic inflammation. Here the authors show that the activation of anti-inflammatory M2a-subtype macrophages requires the IL4/Irs2/Akt pathway. Due to decreased Irs2 expression this pathway is impaired in obese mice thus leading to a defect in M2a activation.

Abstract Several cellular signaling pathways, including insulin/IGF signaling, are known to be activated in hepatocellular carcinoma (HCC). Here, we investigated the roles of insulin receptor substrate (Irs) 1 and Irs2, both of which are the major molecules to be responsible for transducing insulin/IGF signaling in the liver, in the development of HCC by inducing chemical carcinogenesis using diethylnitrosamine (DEN) in mice. The Irs1 mRNA and protein expressions were upregulated in the tumors, along with enhanced insulin signaling. Liver-specific Irs1-knockout (LIrs1KO) mice exhibited suppression of DEN-induced HCC development, accompanied by reduced cancer cell proliferative activity and reduced activation of Akt. Gene expression analyses revealed that the tumors in the DEN-treated LIrs1KO mice showed modest metabolic alterations during hepatocarcinogenesis as well as decreased inflammation and invasion potentials. On the other hand, liver-specific Irs2-knockout (LIrs2KO) mice showed a similar pattern of HCC development to the DEN-treated control wild-type mice. Based on the knowledge that Wnt/β-catenin signaling is activated in HCC, we focused on Wnt/β-catenin signaling and demonstrated that Irs1 expression was induced by Wnt3a stimulation in the primary hepatocytes, associated with insulin-stimulated Akt activation. These data suggest that upregulated Irs1 by Wnt/β-catenin signaling plays a crucial role in the progression of HCC.

Abstract Skin fibrosis in systemic sclerosis (SSc) is accompanied by attrition of dermal white adipose tissue (dWAT) and reduced levels of circulating adiponectin. Since adiponectin has potent regulatory effects on fibroblasts, we sought to assess adiponectin signaling in SSc skin biopsies, and evaluate fibrosis in mice with adiponectin gain- and loss-of-function mutations. Furthermore, we investigated the effects and mechanism of action of agonist peptides targeting adiponectin receptors in vitro and in vivo. We found that adiponectin pathway activity was significantly reduced in a subset of SSc skin biopsies. Mice lacking adiponectin mounted an exaggerated dermal fibrotic response, while transgenic mice with constitutively elevated adiponectin showed selective dWAT expansion and protection from skin and peritoneal fibrosis. Adiponectin receptor agonists abrogated ex vivo fibrotic responses in explanted normal and SSc fibroblasts and in 3D human skin equivalents, in part by attenuating focal adhesion complex assembly, and prevented and reversed experimentally-induced organ fibrosis in mice. These results implicate aberrant adiponectin pathway activity in skin fibrosis, identifying a novel function for this pleiotropic adipokine in regulation of tissue remodeling. Restoring adiponectin signaling in SSc patients therefore might represent an innovative pharmacological strategy for intractable organ fibrosis.

Summary: Complex interactions between immune cells are an important component in the induction of obesity. Here, we show that Il2rg−/−Rag2−/− mice lacking all lymphocytes are resistant to diet-induced obesity. Transplantation of bone marrow cells from Rag2−/− mice, which lack only acquired immune cells, into Il2rg−/−Rag2−/− mice abolishes this resistance, indicating a role for innate lymphoid cells (ILCs) in this process. Mice lacking ILC2 or ILC3 cells, but not natural killer cells, are resistant to obesity. Adoptive transfer of naive ILC2s isolated from the small intestine (SI), but not ILC2s from white adipose tissue (WAT), restores the induction of diet-induced obesity in Il2rg−/−Rag2−/− mice. Analysis of transcriptional differences reveals that SI-ILC2s express higher levels of IL-2 than do WAT-ILC2s and that blockade of IL-2 signaling impairs weight gain and reduces the populations of ILC2s and ILC3s in the SI, suggesting a role for the IL-2/ILC2/3 axis in the induction of obesity. : Innate lymphoid cells (ILCs) are recently identified lymphocyte populations characterized by the lack of antigen-specific receptors. Sasaki et al. demonstrate the involvement of ILCs in the induction of diet-induced obesity. Specifically, they show that small intestinal ILC2s, but not white adipose tissue ILC2s, are involved in the induction of obesity. Keywords: obesity, high-fat diet, innate lymphoid cells, ILC2, ILC3, small intestine, white adipose tissue, common gamma chain, γc, interleukin-2

Background: Fusobacterium nucleatum, which is associated with periodontitis and gingivitis, has been detected in colorectal cancer (CRC). Methods: We evaluated the bactericidal effect of deep ultraviolet (DUV) light-emitting diode (LED) light therapy on F. nucleatum both qualitatively and quantitatively. Two DUV-LEDs with peak wavelengths of 265 and 280-nm were used. DNA damage to F. nucleatum was evaluated by the production of cyclobutane pyrimidine dimers (CPD) and pyrimidine (6–4) pyrimidone photoproducts (6–4PP). Results: DUV-LEDs showed a bactericidal effect on F. nucleatum. No colony growth was observed after 3 min of either 265 nm or 280 nm DUV-LED irradiation. The survival rates of F. nucleatum under 265 nm DUV-LED light irradiation dropped to 0.0014% for 10 s and to 0% for 20 s irradiation. Similarly, the survival rate of F. nucleatum under 280 nm DUV-LED light irradiation dropped to 0.00044% for 10 s and 0% for 20 s irradiation. The irradiance at the distance of 35 mm from the DUV-LED was 0.265 mW/cm2 for the 265 nm LED and 0.415 mW/cm2 for the 280 nm LED. Thus, the radiant energy for lethality was 5.3 mJ/cm2 for the 265 nm LED and 8.3 mJ/cm2 for the 280 nm LED. Amounts of CPD and 6–4PP in F. nucleatum irradiated with 265 nm DUV-LED light were 6.548 ng/µg and 1.333 ng/µg, respectively. Conclusions: DUV-LED light exerted a bactericidal effect on F. nucleatum by causing the formation of pyrimidine dimers indicative of DNA damage. Thus, DUV-LED light therapy may have the potential to prevent CRC.

Type 2 diabetes and obesity are associated with increased hepatic gluconeogenesis and lipogenesis, known as selective insulin resistance. Here Kubota et al. explain selective insulin resistance in the liver with the zonal distribution and selective insulin-mediated regulation of Irs1 and Irs2.

Objectives. To evaluate the abdominal visceral fat area (VFA), we developed novel ultrasonographic (US) methods for estimating. Methods. 100 male volunteers were recruited, and their VFA was calculated by two novel US methods, the triangle method and the ellipse method. The VFA calculated by these methods was compared with the VFA calculated by CT. Results. Both the VFA calculated by the triangle method (r=0.766, p

Peroxisome proliferator-activated receptor γ (PPARγ ), a nuclear receptor superfamily member, plays a major role in lipid metabolism and insulin sensitivity. We investigated the role of PPARγ in colonic epithelial cell turnover and carcinogenesis in colon because PPARγ is strongly expressed in colonic epithelium. Administration of PPARγ agonists suppressed epithelial cell turnover in mice. Expression level of β-catenin protein, a key molecule in carcinogenesis, was increased in mouse colon treated with PPARγ ligands. A direct interaction between β-catenin and PPARγ in cultured cell lines and colonic epithelium in mice was observed. Ligand-activated PPARγ ligand directly interacts with β-catenin, retaining it in the cytosol and reducing β-catenin / T cell factor (TCF) transcriptional activity that is functionally important on aberrant crypt foci (ACF) formation. PPARγ hetero-deficiency promoted the induction of ACF, but had no effect on the incidence of colonic polyps. These results indicate that PPARγ regulates colonic epithelial cell turnover via direct interactions with β-catenin, resulting in inhibition of β-catenin–mediated transcriptional pathways that are involved in promoting cell proliferation. Our findings suggest that PPARγ plays a role as a physiological regulator of colonic epithelial cell turnover and consequently predisposition to the development of colon cancer in early stage. Keywords:: peroxisome proliferator-activated receptor γ (PPARγ ), epithelial cell turnover, β-catenin, colon cancer

Some of insulin's functions, including glucose/lipid metabolism, satiety and neuroprotection, involve the alteration of brain activities. Insulin could signal to the brain via penetrating through the blood-brain barrier and acting on the vagal afferents, while the latter remains unproved. This study aimed to clarify whether insulin directly regulates the nodose ganglion neurons (NGNs) of vagal afferents in mice. NGs expressed insulin receptor (IR) and insulin receptor substrate-2 (IRS2) mRNA, and some of NGNs were immunoreactive to IR. In patch-clamp and fura-2 microfluorometric studies, insulin (10(-12)∼10(-6) M) depolarized and increased cytosolic Ca(2+) concentration ([Ca(2+)]i) in single NGNs. The insulin-induced [Ca(2+)]i increases were attenuated by L- and N-type Ca(2+) channel blockers, by phosphatidylinositol 3 kinase (PI3K) inhibitor, and in NGNs from IRS2 knockout mice. Half of the insulin-responsive NGNs contained cocaine- and amphetamine-regulated transcript. Neuronal fibers expressing IRs were distributed in/around pancreatic islets. The NGNs innervating the pancreas, identified by injecting retrograde tracer into the pancreas, responded to insulin with much greater incidence than unlabeled NGNs. Insulin concentrations measured in pancreatic vein was 64-fold higher than that in circulation. Elevation of insulin to 10(-7) M recruited a remarkably greater population of NGNs to [Ca(2+)]i increases. Systemic injection of glibenclamide rapidly released insulin and phosphorylated AKT in NGs. Furthermore, in IRS2 knockout mice, insulin action to suppress [Ca(2+)]i in orexigenic ghrelin-responsive neurons in hypothalamic arcuate nucleus was intact while insulin action on NGN was markedly attenuated, suggesting a possible link between impaired insulin sensing by NGNs and hyperphagic obese phenotype in IRS2 knockout mice These data demonstrate that insulin directly activates NGNs via IR-IRS2-PI3K-AKT-cascade and depolarization-gated Ca(2+) influx. Pancreas-innervating NGNs may effectively sense dynamic changes of insulin released in response to nutritional states. These interactions could serve to convey the changes in pancreatic and systemic insulin to the brain.

The insulin/IGF-1 signaling (IIS) regulates a wide range of biological processes, including aging and lifespan, and has also been implicated in the pathogenesis of Alzheimer's disease (AD). We and others have reported that reduced signaling by genetic ablation of the molecules involved in IIS (e.g., insulin receptor substrate 2 [IRS-2]) markedly mitigates amyloid plaque formation in the brains of mouse models of AD, although the molecular underpinnings of the amelioration remain unsolved. Here, we revealed, by a transcriptomic analysis of the male murine cerebral cortices, that the expression of genes encoding extracellular matrix (ECM) was significantly upregulated by the loss of IRS-2. Insulin signaling activity negatively regulated the phosphorylation of Smad2 and Smad3 in the brain, and suppressed TGF-β/Smad-dependent expression of a subset of ECM genes in brain-derived cells. The ECM proteins inhibited Aβ fibril formation in vitro, and IRS-2 deficiency suppressed the aggregation process of Aβ in the brains of male APP transgenic mice as revealed by injection of aggregation seeds in vivo. Our results propose a novel mechanism in AD pathophysiology whereby IIS modifies Aβ aggregation and amyloid pathology by altering the expression of ECM genes in the brain. [ABSTRACT FROM AUTHOR]

Adipose tissue is central to regulation of energy homeostasis. Adaptive thermogenesis, which relies on mitochondrial oxidative phosphorylation (Ox-Phos), dissipates energy to counteract obesity. On the other hand, chronic inflammation in adipose tissue is linked to type 2 diabetes and obesity. Here, we show that nuclear factor I-A (NFIA), a transcriptional regulator of brown and beige adipocytes, improves glucose homeostasis by upregulation of Ox-Phos and reciprocal downregulation of inflammation. Mice with transgenic expression of NFIA in adipocytes exhibited improved glucose tolerance and limited weight gain. NFIA up-regulates Ox-Phos and brown-fat-specific genes by enhancer activation that involves facilitated genomic binding of PPAR?. In contrast, NFIA in adipocytes, but not in macrophages, down-regulates proinflammatory cytokine genes to ameliorate adipose tissue inflammation. NFIA binds to regulatory region of the Ccl2 gene, which encodes proinflammatory cytokine MCP-1 (monocyte chemoattractant protein-1), to down-regulate its transcription. CCL2 expression was negatively correlated with NFIA expression in human adipose tissue. These results reveal the beneficial effect of NFIA on glucose and body weight homeostasis and also highlight previously unappreciated role of NFIA in suppressing adipose tissue inflammation. [ABSTRACT FROM AUTHOR]