Lgr5+ intestinal stem cells generate enterocytes and secretory cells. Secretory lineage commitment requires Notch silencing. The Notch ligand Dll1 is expressed by a subset of immediate stem cell ...daughters. Lineage tracing in Dll1(GFP-ires-CreERT2) knock-in mice reveals that single Dll1(high) cells generate small, short-lived clones containing all four secretory cell types. Lineage specification thus occurs in immediate stem cell daughters through Notch lateral inhibition. Cultured Dll1(high) cells form long-lived organoids (mini-guts) on brief Wnt3A exposure. When Dll1(high) cells are genetically marked before tissue damage, stem cell tracing events occur. Thus, secretory progenitors exhibit plasticity by regaining stemness on damage.
Aim: Diameter, intima–media thickness (IMT), and flow parameters, including resistance index (RI) and pulsatility index (PI), in the common carotid artery (CCA) are markers of arterial remodeling, ...atherosclerosis, and vascular resistance, respectively. We investigated the differences among these markers in association with plasma glucose level, serum insulin level, and insulin resistance in participants without cardiovascular disease.Methods: CCA parameters (including the CCA interadventitial diameter and mean IMT at the time of 75-g oral glucose tolerance testing) were assessed in 4218 participants. RI and PI were assessed in 3380 of these participants. To assess plasma glucose and serum immunoreactive insulin profiles during oral glucose tolerance testing, we used the total areas under the curves (AUCglu and AUCins, respectively). We used the homeostasis model assessment of insulin resistance (HOMA-IR) and the Matsuda index to assess insulin resistance. Insulin secretion was assessed with the HOMA-β.Results: AUCglu was significantly associated with CCA interadventitial diameter (β=0.048, P＜0.001), RI (β=0.144, P＜0.001), and PI (β=0.103, P＜0.001) but not with mean IMT. AUCins (β=−0.064, P＜0.001) and HOMA-β (β=−0.054, P＜0.001) were significantly and negatively associated with CCA interadventitial diameter, but not with mean IMT. Both HOMA-IR and Matsuda index were significantly associated with RI and PI.Conclusions: These findings indicate that all CCA parameters except IMT are associated with impaired glucose metabolism in patients without cardiovascular disease.
Background The interrelationships among the different stages of impaired glucose metabolism, insulin resistance, and hypertension are not fully understood. Methods and Results We investigated the ...impact of insulin resistance, plasma glucose, and serum immunoreactive insulin levels on hypertension in 19 166 participants with different stages of impaired glucose metabolism (7114 normal fasting glucose/normal glucose tolerance, 3543 isolated impaired fasting glucose IFG, 2089 isolated impaired glucose tolerance, 2922 IFG plus impaired glucose tolerance, and 3498 diabetes mellitus) determined by 75-g oral glucose tolerance tests. Participants were recruited from examinees who finished a general health checkup for atomic bomb survivors between 1982 and 2017. The profiles of plasma glucose and immunoreactive insulin during oral glucose tolerance tests were assessed using the total area under the curve. Insulin resistance was assessed using the homeostasis model assessment of insulin resistance. The rate of hypertension increased from 36.3% in participants with normal fasting glucose/normal glucose tolerance to 50.1%, 50.8%, 58.3%, and 63.8% in participants with isolated IFG, isolated impaired glucose tolerance, IFG plus impaired glucose tolerance, and diabetes mellitus, respectively. Homeostasis model assessment of insulin resistance was associated with hypertension regardless of the presence and the degree of impaired glucose metabolism. Furthermore, fasting plasma glucose and serum immunoreactive insulin levels and areas under the curve for plasma glucose and immunoreactive insulin during oral glucose tolerance tests were associated with hypertension in normal fasting glucose/normal glucose tolerance and isolated IFG, but such a relationship was diminished in other types of prediabetes and diabetes mellitus. Conclusions The prevalence of hypertension increases with worsening stages of impaired glucose metabolism; however, hyperglycemia and hyperinsulinemia are significant contributors to the presence of hypertension only in the early stages of impaired insulin metabolism.
Leucine-rich repeat-containing G-protein coupled receptor 5-positive (Lgr5⁺) stem cells reside at crypt bottoms of the small and large intestine. Small intestinal Paneth cells supply Wnt3, EGF, and ...Notch signals to neighboring Lgr5⁺ stem cells. Whereas the colon lacks Paneth cells, deep crypt secretory (DCS) cells are intermingled with Lgr5⁺ stem cells at crypt bottoms. Here, we report regenerating islet-derived family member 4 (Reg4) as a marker of DCS cells. To investigate a niche function, we eliminated DCS cells by using the diphtheria-toxin receptor gene knocked into the murine Reg4 locus. Ablation of DCS cells results in loss of stem cells from colonic crypts and disrupts gut homeostasis and colon organoid growth. In agreement, sorted Reg4⁺ DCS cells promote organoid formation of single Lgr5⁺ colon stem cells. DCS cells can be massively produced from Lgr5⁺ colon stem cells in vitro by combined Notch inhibition and Wnt activation. We conclude that Reg4⁺ DCS cells serve as Paneth cell equivalents in the colon crypt niche.
Cycling intestinal Lgr5⁺ stem cells are intermingled with their terminally differentiated Paneth cell daughters at crypt bottoms. Paneth cells provide multiple secreted (e.g., Wnt, EGF) as well as ...surface-bound (Notch ligand) niche signals. Here we show that ablation of Paneth cells in mice, using a diphtheria toxin receptor gene inserted into the P-lysozyme locus, does not affect the maintenance of Lgr5⁺ stem cells. Flow cytometry, single-cell sequencing, and histological analysis showed that the ablated Paneth cells are replaced by enteroendocrine and tuft cells. As these cells physically occupy Paneth cell positions between Lgr5 stem cells, they serve as an alternative source of Notch signals, which are essential for Lgr5⁺ stem cell maintenance. Our combined in vivo results underscore the adaptive flexibility of the intestine in maintaining normal tissue homeostasis.
Primary sclerosing cholangitis (PSC) is a chronic inflammatory liver disease and its frequent complication with ulcerative colitis highlights the pathogenic role of epithelial barrier dysfunction. ...Intestinal barrier dysfunction has been implicated in the pathogenesis of PSC, yet its underlying mechanism remains unknown. Here, we identify Klebsiella pneumonia in the microbiota of patients with PSC and demonstrate that K. pneumoniae disrupts the epithelial barrier to initiate bacterial translocation and liver inflammatory responses. Gnotobiotic mice inoculated with PSC-derived microbiota exhibited T helper 17 (T
17) cell responses in the liver and increased susceptibility to hepatobiliary injuries. Bacterial culture of mesenteric lymph nodes in these mice isolated K. pneumoniae, Proteus mirabilis and Enterococcus gallinarum, which were prevalently detected in patients with PSC. A bacterial-organoid co-culture system visualized the epithelial-damaging effect of PSC-derived K. pneumoniae that was associated with bacterial translocation and susceptibility to T
17-mediated hepatobiliary injuries. We also show that antibiotic treatment ameliorated the T
17 immune response induced by PSC-derived microbiota. These results highlight the role of pathobionts in intestinal barrier dysfunction and liver inflammation, providing insights into therapeutic strategies for PSC.
The gastric corpus epithelium is the thickest part of the gastrointestinal tract and is rapidly turned over. Several markers have been proposed for gastric corpus stem cells in both isthmus and base ...regions. However, the identity of isthmus stem cells (IsthSCs) and the interaction between distinct stem cell populations is still under debate. Here, based on unbiased genetic labeling and biophysical modeling, we show that corpus glands are compartmentalized into two independent zones, with slow-cycling stem cells maintaining the base and actively cycling stem cells maintaining the pit-isthmus-neck region through a process of “punctuated” neutral drift dynamics. Independent lineage tracing based on Stmn1 and Ki67 expression confirmed that rapidly cycling IsthSCs maintain the pit-isthmus-neck region. Finally, single-cell RNA sequencing (RNA-seq) analysis is used to define the molecular identity and lineage relationship of a single, cycling, IsthSC population. These observations define the identity and functional behavior of IsthSCs.
Display omitted
•Marker-free lineage tracing reveals two types of stem cells in the gastric corpus•Actively cycling isthmus stem cells follow “punctuated” neutral drift dynamics•Stmn1 and Ki67 lineage tracing confirms the active cycling of isthmus stem cells•Single-cell RNA-seq defines identity and lineage relationship of isthmus stem cells
Using lineage-tracing assays and single-cell gene expression profiling, Han et al. show that the mouse gastric corpus gland is compartmentalized, with base and isthmus regions supported by two separate independent stem cell populations. Isthmus stem cells are rapidly cycling, with a broad expression signature, and undergo “punctuated” neutral drift dynamics.
A low-temperature poly-Si film with 99.8% {100} texture in the surface normal direction within 10° is obtained by single-scan continuous-wave laser lateral crystallization of 60nm-thick a-Si without ...a seed at room temperature in air. This texture extends over the entire melted width of 105μm except for narrow edge regions and is maintained for the full scan length of 1.8mm. Highly {100}-oriented films in the surface-normal direction are obtained at the low net laser power P(1-R) of 1–1.25W above the threshold for the lateral grain growth, where P is the incident total power, and R is the reflectivity of the sample. A second power threshold exists where the degree of the {100} surface-normal texture begins to decrease above the first threshold for lateral grains. Above the second threshold, the percentage of the {100} surface-normal texture decreases linearly with the increasing P(1-R) at the same slope of 20% in 0.1W change for all the samples with different cap thicknesses.
•99.8% {100} oriented poly-Si film is realized by a CW laser crystallization.•The {100} film is obtained with a lateral growth at a lower power.•The {100} texture extends over the entire melted width.•2nd power threshold exists, where degree of {100} texture begins to decrease.Degree of {100} texture decreases linearly with power above the 2nd threshold.
PDF
