Antibiotic effects on gut microbiota modulate diet-induced metabolic dysfunction-associated steatohepatitis development in C57BL/6 mice.

The potential involvement of the gut microbiota in metabolic dysfunction-associated steatohepatitis (MASH) pathogenesis has garnered increasing attention. In this study, we elucidated the link between high-fat/cholesterol/cholate-based (iHFC)#2 diet-induced MASH progression and gut microbiota in C57BL/6 mice using antibiotic treatments. Treatment with vancomycin (VCM), which targets gram-positive bacteria, exacerbated the progression of liver damage, steatosis, and fibrosis in iHFC#2-fed C57BL/6 mice. The expression levels of inflammation- and fibrosis-related genes in the liver significantly increased after VCM treatment for 8 weeks. F4/80+ macrophage abundance increased in the livers of VCM-treated mice. These changes were rarely observed in the iHFC#2-fed C57BL/6 mice treated with metronidazole, which targets anaerobic bacteria. A16S rRNA sequence analysis revealed a significant decrease in α-diversity in VCM-treated mice compared with that in placebo-treated mice, with Bacteroidetes and Firmicutes significantly decreased, while Proteobacteria and Verrucomicrobia increased markedly. Finally, VCM treatment dramatically altered the level and balance of bile acid (BA) composition in iHFC#2-fed C57BL/6 mice. Thus, the VCM-mediated exacerbation of MASH progression depends on the interaction between the gut microbiota, BA metabolism, and inflammatory responses in the livers of iHFC#2-fed C57BL/6 mice.

Impacts of liver macrophages, gut microbiota, and bile acid metabolism on the differences in iHFC diet-induced MASH progression between TSNO and TSOD mice.

BACKGROUND: Tsumura-Suzuki non-obese (TSNO) mice exhibit a severe form of metabolic dysfunction-associated steatohepatitis (MASH) with advanced liver fibrosis upon feeding a high-fat/cholesterol/cholate-based (iHFC) diet. Another ddY strain, Tsumura-Suzuki diabetes obese (TSOD) mice, are impaired in the progression of iHFC diet-induced MASH. AIM: To elucidate the underlying mechanisms contributing to the differences in MASH progression between TSNO and TSOD mice. METHODS: We analyzed differences in the immune system, gut microbiota, and bile acid metabolism in TSNO and TSOD mice fed with a normal diet (ND) or an iHFC diet. RESULTS: TSOD mice had more anti-inflammatory macrophages in the liver than TSNO mice under ND feeding, and were impaired in the iHFC diet-induced accumulation of fibrosis-associated macrophages and formation of histological hepatic crown-like structures in the liver. The gut microbiota of TSOD mice also exhibited a distinct community composition with lower diversity and higher abundance of Akkermansia muciniphila compared with that in TSNO mice. Finally, TSOD mice had lower levels of bile acids linked to intestinal barrier disruption under iHFC feeding. CONCLUSIONS: The dynamics of liver macrophage subsets, and the compositions of the gut microbiota and bile acids at steady state and post-onset of MASH, had major impacts on MASH development.

The innate immune receptor RP105 promotes metabolic syndrome by altering gut microbiota composition and intestinal barrier function.

Radioprotective 105 (RP105) plays a key role in the development of high-fat diet (HFD)-induced metabolic disorders; however, the underlying mechanisms remain to be understood. Here, we aimed to uncover whether RP105 affects metabolic syndrome through the modification of gut microbiota. We confirmed that body weight gain and fat accumulation by HFD feeding were suppressed in Rp105-/- mice. Fecal microbiome transplantation from HFD-fed donor Rp105-/- mice into HFD-fed recipient wild-type mice significantly improved various abnormalities associated with metabolic syndrome, including body weight gain, insulin resistance, hepatic steatosis, macrophage infiltration and inflammation in the adipose tissue. In addition, HFD-induced intestinal barrier dysfunction was attenuated by fecal microbiome transplantation from HFD-fed donor Rp105-/- mice. A 16S rRNA sequence analysis indicated that RP105 modified gut microbiota composition and was involved in the maintenance of its diversity. Thus, RP105 promotes metabolic syndrome by altering gut microbiota composition and intestinal barrier function.

Impact of Vancomycin Treatment and Gut Microbiota on Bile Acid Metabolism and the Development of Non-Alcoholic Steatohepatitis in Mice.

The potential roles of the gut microbiota in the pathogenesis of non-alcoholic fatty liver disease, including non-alcoholic steatohepatitis (NASH), have attracted increased interest. We have investigated the links between gut microbiota and NASH development in Tsumura-Suzuki non-obese mice fed a high-fat/cholesterol/cholate-based (iHFC) diet that exhibit advanced liver fibrosis using antibiotic treatments. The administration of vancomycin, which targets Gram-positive organisms, exacerbated the progression of liver damage, steatohepatitis, and fibrosis in iHFC-fed mice, but not in mice fed a normal diet. F4/80+-recruited macrophages were more abundant in the liver of vancomycin-treated iHFC-fed mice. The infiltration of CD11c+-recruited macrophages into the liver, forming hepatic crown-like structures, was enhanced by vancomycin treatment. The co-localization of this macrophage subset with collagen was greatly augmented in the liver of vancomycin-treated iHFC-fed mice. These changes were rarely seen with the administration of metronidazole, which targets anaerobic organisms, in iHFC-fed mice. Finally, the vancomycin treatment dramatically modulated the level and composition of bile acid in iHFC-fed mice. Thus, our data demonstrate that changes in inflammation and fibrosis in the liver by the iHFC diet can be modified by antibiotic-induced changes in gut microbiota and shed light on their roles in the pathogenesis of advanced liver fibrosis.

Roles of Macrophages in Advanced Liver Fibrosis, Identified Using a Newly Established Mouse Model of Diet-Induced Non-Alcoholic Steatohepatitis.

Macrophages play critical roles in the pathogenesis of non-alcoholic steatohepatitis (NASH). However, it is unclear which macrophage subsets are critically involved in the development of inflammation and fibrosis in NASH. In TSNO mice fed a high-fat/cholesterol/cholate-based diet, which exhibit advanced liver fibrosis that mimics human NASH, we found that Kupffer cells (KCs) were less abundant and recruited macrophages were more abundant, forming hepatic crown-like structures (hCLS) in the liver. The recruited macrophages comprised two subsets: CD11c+/Ly6C- and CD11c-/Ly6C+ cells. CD11c+ cells were present in a mesh-like pattern around the lipid droplets, constituting the hCLS. In addition, CD11c+ cells colocalized with collagen fibers, suggesting that this subset of recruited macrophages might promote advanced liver fibrosis. In contrast, Ly6C+ cells were present in doughnut-like inflammatory lesions, with a lipid droplet in the center. Finally, RNA sequence analysis indicates that CD11c+/Ly6C- cells promote liver fibrosis and hepatic stellate cell (HSC) activation, whereas CD11c-/Ly6C+ cells are a macrophage subset that play an anti-inflammatory role and promote tissue repair in NASH. Taken together, our data revealed changes in liver macrophage subsets during the development of NASH and shed light on the roles of the recruited macrophages in the pathogenesis of advanced fibrosis in NASH.

Skin surface material for detecting human papillomavirus infection of skin warts.

Warts, caused by human papillomavirus (HPV) infection, have various clinical presentations, making them difficult to differentiate from clavus, callus, and sometimes, squamous cell carcinoma. Although skin biopsies are the gold standard, a less-invasive method of examining these lesions is desired. Ninety patients with warts and related diseases, such as clavus and callus, were recruited to explore new differentiation methods using the surface of the warts. DNA was extracted from three types of specimens in each case: surface swab, shaved hyperkeratotic scale, and post-shaved surface swab. Total DNA was successfully extracted from these three specimens and was sufficient for subsequent HPV DNA detection. We analyzed samples for the HPV type and HPV viral load using polymerase chain reaction (PCR). Fifty-five cases were PCR-positive, and HPV1a, 2a, 4, 27, 57, and 65 were detected. The amount of HPV1a DNA produced was significantly greater than that of other HPV types. Regarding the correlation between the clinical diagnosis and HPV detection, the positive agreement rate was 90.9%, the negative agreement rate was 40.0%, and the overall agreement rate was 71.1%. Ten of the 21 cases clinically diagnosed as plantar warts were PCR-negative, especially in elderly patients. This suggests that it is difficult to distinguish plantar warts from clavus and callus in clinical practice. Although the amount of HPV DNA in the removed keratinization scale was highest for all HPV types, HPV detection by swabbing before and after shaving is also useful for follow-up as well as for differential diagnosis.

Dynamics of Liver Macrophage Subsets in a Novel Mouse Model of Non-Alcoholic Steatohepatitis Using C57BL/6 Mice.

Macrophages are critical for the development of non-alcoholic steatohepatitis (NASH). Our previous findings in TSNO mouse livers showed that an iHFC (high-fat/cholesterol/cholate) diet induced liver fibrosis similar to human NASH and led to the accumulation of distinct subsets of macrophage: CD11c+/Ly6C- and CD11c-/Ly6C+ cells. CD11c+/Ly6C- cells were associated with the promotion of advanced liver fibrosis in NASH. On the other hand, CD11c-/Ly6C+ cells exhibited an anti-inflammatory effect and were involved in tissue remodeling processes. This study aimed to elucidate whether an iHFC diet with reduced cholic acid (iHFC#2 diet) induces NASH in C57BL/6 mice and examine the macrophage subsets accumulating in the liver. Histological and quantitative real-time PCR analyses revealed that the iHFC#2 diet promoted inflammation and fibrosis indicative of NASH in the livers of C57BL/6 mice. Cell numbers of Kupffer cells decreased and recruited macrophages were accumulated in the livers of iHFC#2 diet-fed C57BL/6 mice. Notably, the iHFC#2 diet resulted in the accumulation of three macrophage subsets in the livers of C57BL/6 mice: CD11c+/Ly6C-, CD11c-/Ly6C+, and CD11c+/Ly6C+ cells. However, CD11c+/Ly6C+ cells were not distinct populations in the iHFC-fed TSNO mice. Thus, differences in cholic acid content and mouse strain affect the macrophage subsets that accumulate in the liver.

Xeroderma pigmentosum complementation group G patient with a novel homozygous missense mutation and no neurological abnormalities.

We describe an unusual xeroderma pigmentosum (XP) patient with a mutation in XP complementation group G, representing only the third reported Japanese XP-G patient. A 40-year-old men (XP3HM), born from consanguineous parents experienced sun sensitivity and pigmentary changes of sun-exposed skin since childhood. He developed a squamous cell carcinoma on his lower lip at the age of 40. He has neither neurological abnormalities nor Cockayne syndrome. The primary fibroblasts of the patient were hypersensitive to killing by UV (D(0) = 0.6 J/m(2)) and the post-UV unscheduled DNA synthesis was 8% of normal. Host cell reactivation complementation analysis implicated XP complementation group G. We identified a novel homozygous mutation (c.194T>C) in a conserved portion of the XPG(ERCC5) gene, resulting in a predicted amino acid change; p.L65P. We confirmed that this genetic change reduced DNA repair thus linking this mutation to increased skin cancer.

Cutaneous manifestations and histological features of microscopic polyangiitis.

Purpura and livedo are common cutaneous manifestations of microscopic polyangiitis (MPA); however, only a few clinical analyses focusing on the relationship between clinical symptoms and the affected vessels in the skin have been reported. We herein report the cutaneous manifestations and histological features of four patients with MPA. In two patients, a Henoch-Shönlein purpura-like eruption developed with necrotizing vasculitis localized in the upper dermis. The other two patients presented with livedo racemosa; with histological findings of necrotizing vasculitis of the small vessels around the muscle fibers or from the deep dermis to subcutaneous tissue. Two patients' cases were complicated by systemic sclerosis and had poor prognoses. MPA can present with various cutaneous manifestations. Additional research is required to ascertain the relationship between the prognosis and the affected vessels.

Lupus pernio with multiple bone cysts in the fingers.

A 32-year-old Japanese man presented with a 3-year history of purple reddish, and painful swelling of his fingers along with indurated erythema on his nose and ears. He was diagnosed as having sarcoidosis 8 years prior because of uveitis and bilateral hilar lymphadenopathy. X-rays of the hands revealed multiple cystic lesions in the phalanges. Histological examination of the ear revealed epithelioid cell granulomas in the dermis. Oral prednisolone 20 mg/day improved his finger swelling and pain; however, his finger deformities and erythema remain unchanged. Bone involvement is sometimes seen in sarcoidosis and the hands are the most frequently affected areas. The frequency of bone involvement is higher in lupus pernio in comparison with other types of skin sarcoidosis. Systemic corticosteroids could be the first choice of treatment to relieve the symptoms.