Clinicopathological features of graft versus host disease-associated myositis.

BACKGROUND AND OBJECTIVE: Chronic graft versus host disease (GVHD)-associated myositis targeting skeletal muscle is a relatively rare but potentially debilitating complication following allogeneic hematopoietic stem cell transplantation (HSCT). We reviewed the clinicopathological features of GVHD-associated myositis among patients receiving allogeneic HSCT to elucidate the cellular pathogenesis. METHODS: We retrospectively reviewed clinical data and muscle biopsy results from 17 consecutive patients diagnosed with GVHD-associated myositis at our institution between 1995 and 2019. Immunostaining findings of GVHD-associated myositis were compared to those of patients with anti-tRNA-synthetase antibody-associated myopathy (ASM) (n = 13) and dermatomyositis (DM) (n = 12). RESULTS: The majority of patients with GVHD-associated myositis showed subacute or chronic progression of mild to moderate limb weakness together with elevated serum creatine kinase. These patients also exhibited mild C-reactive protein elevation but were negative for myositis-related autoantibodies. Programmed death-1 (PD-1)-positive cells were observed in muscle interstitium adjacent to myofibers expressing human leukocyte antigen (HLA)-DR. The interstitium was also HLA-DR-positive, similar to biopsy samples from ASM patients but not DM patients. The proportions of HLA-DR-positive muscle fibers and PD-1-positive interstitial cells were significantly higher in GVHD and ASM samples than DM samples. The PD-1-positive cells were mostly CD-8-positive lymphocytes. DISCUSSION: GVHD-associated myositis is characterized by HLA-DR-positive myofibers and infiltration of PD-1-positive lymphocytes. These features distinguish GVHD-associated myositis from DM but not from ASM.

Metabolome and transcriptome analysis on muscle of sporadic inclusion body myositis.

OBJECTIVE: Sporadic inclusion body myositis (sIBM) is the most common acquired myopathy in patients older than 50 years of age. sIBM is hardly responds to any immunosuppressing theraphies, and its pathophysiology remains elusive. This study aims to explore pathogenic pathways underlying sIBM and identify novel therapeutic targets using metabolomic and transcriptomic analyses. METHODS: In this retrospective observational study, we analyzed biopsied muscle samples from 14 sIBM patients and six non-diseased subjects to identify metabolic profiles. Frozen muscle samples were used to measure metabolites with cation and anion modes of capillary electrophoresis time of flight mass spectrometry. We validated the metabolic pathway altered in muscles of sIBM patients through RNA sequencing and histopathological studies. RESULTS: A total of 198 metabolites were identified. Metabolomic and transcriptomic analyses identified specific metabolite changes in sIBM muscle samples. The pathways of histamine biosynthesis and certain glycosaminoglycan biosynthesis were upregulated in sIBM patients, whereas those of carnitine metabolism and creatine metabolism were downregulated. Histopathological examination showed infiltration of mast cells and deposition of chondroitin sulfate in skeletal muscle samples, supporting the results of metabolomic and transcriptomic analyses. INTERPRETATION: We identified alterations of several metabolic pathways in muscle samples of sIBM patients. These results suggest that mast cells, chondroitin sulfate biosynthesis, carnitine, and creatine play roles in sIBM pathophysiology.

Clinical implication of denervation in sporadic inclusion body myositis.

INTRODUCTION: Sporadic inclusion body myositis (sIBM) is often accompanied by signs suggestive of denervation on electromyography (EMG), which mimics neurogenic disorders. Hence, the current study aimed to assess reinnervation after denervation in sIBM and its clinical impllcation. METHODS: We retrospectively examined consecutive muscle biopsy specimens collected from 109 sIBM patients who were referred to our institution for diagnostic muscle biopsy from 2001 to 2018. Reinnervation after denervation in sIBM patients was assessed via muscle biopsy and EMG. The levels of acetylcholine receptor subunit γ (Chrng) and muscle-specific kinase (MuSK) mRNA, which are markers of denervation, were examined using real-time polymerase chain reaction. Response to treatment was defined as an increase of grade 1 or higher in two or more muscle groups as assessed using the Medical Research Council scale. RESULTS: In total, 93 (85.3%) of 109 sIBM patients had reinnervation after denervation on histological examination and/or EMG. The mean disease duration before biopsy was significantly longer in patients with reinnervation after denervation than in those without (p < 0.00001). Patients with denervation had significantly higher levels of Chrng and MuSK mRNA than those without. The proportion of patients who responded to immunosuppressive therapies was smaller in the patients with denervation than those without (p < 0.05). However, there was no significant difference regarding time from onset to using a walking aid between the two groups. DISCUSSION: Reinnervation after denervation is associated with disease duration and short-term response to therapy in individuals with sIBM.

A case of sporadic late-onset nemaline myopathy with monoclonal gammopathy of undetermined significance: long-term observation of neurological symptoms after autologous stem-cell transplantation.

A 47-year-old woman presented with progressive limb weakness. A neurological examination revealed proximal dominant symmetrical muscle weakness in her limbs, and electromyography revealed complex repetitive discharges and short motor unit potentials with positive sharp waves in the biceps. We observed early recruitment in the quadriceps, and laboratory tests revealed normal creatine kinase. Serum protein electrophoresis showed monoclonal IgG-lambda, but the bone marrow aspiration specimen was normal. A muscle biopsy revealed nemaline rod accumulations in the muscle fibers; based on the results, we diagnosed the patient with sporadic late-onset nemaline myopathy with monoclonal gammopathy of undetermined significance (SLONM-MGUS). We administered repeated intravenous immunoglobulin, but her limb weakness continued, and she developed a restrictive ventilatory defect. The patient received melphalan, followed by autologous stem-cell transplantation (ASCT). Her upper extremity strength and respiratory capability improved within one year after ASCT; however, it was not until six years after ASCT that her atrophied lower extremities strengthened. A discrepancy in the timeline of treatment response between the upper or respiratory muscles and the atrophied lower limb was characteristic in the patient, suggesting that the efficacy of ASCT on SLONM-MGUS should be evaluated in the long term, especially in severely atrophied muscles. In addition, this case showed that ASCT for SLOMN-MGUS is an effective treatment option in Asian populations.

[Successful treatment with bortezomib in a patient with systemic primary AL amyloidosis manifesting severe gastrointestinal bleeding].

We present a systemic primary AL amyloidosis patient with severe gastrointestinal bleeding for whom treatment with bortezomib and dexamethasone was very effective. An 83-year-old woman was admitted to our hospital suffering from multiple gastric ulcers with bleeding. She had monoclonal protein (IgG, λ) in her serum. Systemic primary AL amyloidosis was diagnosed. She was also suspected of having amyloid deposition in cardiac muscle, as well as her bladder and intestinal mucosa. However, we were unable to carry out other invasive examinations due to her bleeding tendency. She was treated with bortezomib and dexamethasone. Her bleeding tendency gradually diminished. After one year, the bleeding tendency had completely resolved. However, she still had amyloid deposition in her gastric mucosa and skin.

Urinary oxidative stress markers in young patients with type 1 diabetes.

BACKGROUND: Involvement of oxidative stress in the pathogenesis of diabetic vascular complications has been proposed. However, there are few methods to determine the status of oxidative stress both directly and quantitatively in young patients with type 1 diabetes. METHODS: A total of 27 young patients with type 1 diabetes (mean age +/- SD, 12.6 +/- 4.2 years) with normal renal function and 38 healthy control subjects (13.0 +/- 4.6 years) were investigated. Early morning voiding urine samples were collected. The concentrations of acrolein-lysine adducts, 8-hydroxy-2'-deoxyguanosine (8-OHdG) were determined using competitive enzyme-linked immunosorbent assay, and nitric oxide metabolites were measured using the colorimetric, non-enzymatic assay. RESULTS: Urinary concentrations of 8-OHdG, but not acrolein-lysine adducts and nitric oxide metabolites, were significantly increased in the diabetic group. For diabetic patients, microalbuminuria was significantly correlated with higher concentrations of all three markers. Hemoglobin A(1c) values were significantly correlated with 8-OHdG values. CONCLUSIONS: These findings indicate that increased oxidative stress and the risk of vascular complications may be present at early stages of type 1 diabetes.

Genetic and biochemical properties of streptococcal NAD-glycohydrolase inhibitor.

The gene encoding streptolysin O (slo), a cytolysin of hemolytic streptococci, is transcribed polycistronically from the promoter of the preceding NAD-glycohydrolase (NADase) gene (nga). Between nga and slo, a putative open reading frame (orf1) is located whose function has been totally unknown. Present investigation demonstrated that the orf1 encodes a protein designated as streptococcal NADase inhibitor (SNI). From its nucleotide sequence, SNI was inferred to comprise 161 amino acid residues and the deduced molecular weight was 18,800. This protein was detectable only within cells. Coexpression of SNI was essential for production of streptococcal NADase, and NADase precursor existed as an inactive complex with SNI, in recombinant Escherichia coli. Monomeric NADase and SNI rapidly formed in vitro a stable heterodimer complex in the ratio 1:1, resulting in complete suppression of the hydrolase activity. Unlike other bacterial NADase inhibitors, SNI was thermostable. This protein, coexpressed and complexed with NADase, may protect the producer cocci from exhaustion of NAD.

Expression of recombinant Streptolysin O and specific antibody production.

Streptolysin O (SLO), an oxygen-labile cytolysin, is the cholesterol-binding exotoxin of hemolytic streptococci. Besides microbiological and pathological interests, this cytolysin has been used as a tool for permeabilization of biomembranes. SLO serves as a diagnostic reagent for determination of anti-SLO antibody titer in streptococcal infection. Availability of highly purified SLO, however, has been limited by low yield in streptococcal culture and purification process. Present subcloning of mature-type full-length SLO gene into an expression vector having strictly controllable araBAD promoter enabled efficient production of the cytolysin. Further, anti-SLO antibody with high specificity was obtained by immunizing with purified SLO protein.

The rat enhancer of split- and hairy-related protein-2 gene: hepatic expression, genomic structure, and promoter analysis.

The rat enhancer of split- and hairy-related protein-2 (SHARP-2) is a basic helix-loop-helix transcription factor. The hepatic expression of SHARP-2 mRNA was investigated under various conditions. The level was decreased in the regenerating rat liver and malignant hepatoma cells. In contrast, the expression of SHARP-2 mRNA was induced in rat livers by feeding a high-carbohydrate diet. To analyze the molecular mechanism involved in the regulation of the rat SHARP-2 gene expression, the gene was cloned. It was approximately 6-kb in length and consists of five exons and four introns. To investigate the transcriptional regulatory region of this gene, SHARP-2/firefly luciferase reporter plasmids were transfected into hepatoma cells. A functional analysis of 5(')-deletion constructs revealed that two E box sequences between -160 and -144 are mainly responsible for promoter activity. Although upstream stimulatory factors (USFs) bound to the element in vitro, USF2 failed to stimulate promoter activity from the element using the co-transfection experiment. Therefore, other E box-binding transcription factors differing from USF proteins or USF-associated proteins are necessary for transcriptional stimulation of the rat SHARP-2 gene.

Advanced indications for gonadotropin-releasing hormone (GnRH) analogues in gynecological oncology (review).

Gonadotropin-releasing hormone (GnRH) analogue has beneficial effects on the size and symptoms of endometriosis and uterine leiomyomas as a result of suppressing ovarian steroidogenesis. GnRH analogues are also the preferred treatment for advanced and even metastatic or recurred carcinomas originated from the reproductive tract. The original rationale for a GnRH analogue in the treatment was to block the endogenous gonadotropin and thereby steroid hormone secretion which was thought to stimulate tumor growth. However, more than 80% of ovarian and endometrial cancers express receptors for GnRH, and the analogues inhibit proliferation of the GnRH receptor-bearing tumor cells both in vivo and in vitro, supporting evidence for a direct antiproliferative effect. These receptors could be used for targeted chemotherapy (by tumoricidal agents linked to GnRH analogues) to improve antitumor effects and reduce side effects compared with conventional systemic chemotherapy. In addition to the anticancer action, GnRH analogues act to protect the gonads during radiation and/or chemotherapy by preferentially steering cells into cell cycle arrest with a decline in responsibility to the chemotherapy and radiation. In women who wish to maintain potential fertility, GnRH analogue therapy is successful in preventing the most critical postoperative complication, adhesion formation. The additional unrecognized benefits may add to the advantage of GnRH analogues in cancer management in gynecology.

Selective screening for fatty acid oxidation disorders by tandem mass spectrometry: difficulties in practical discrimination.

In a selective screening for fatty acid oxidation disorders by tandem mass spectrometry, we tested the diagnostic ratios and acylcarnitine concentrations in sera or blood spots, which were reported to be specific to very long-chain acyl CoA dehydrogenase deficiency, carnitine palmitoyltransferase I deficiency, and carnitine palmitoyltransferase II deficiency. While the acylcarnitine profiles in the majority of these patients were typical in the respective disorders, some overlapping of the indices was observed between these patients and the infants, who showed symptoms mainly related to hypoglycemia but did not have the disorders mentioned above. Although the diagnostic ratio of tetradecenoylcarnitine to dodecanoylcarnitine for very long-chain acyl CoA dehydrogenase deficiency seemed to minimize the overlapping in this study, additional measures including careful assessment of clinical data and enzyme assays may be necessary for the diagnosis in atypical cases.

Analysis of zinc-fingers and homeoboxes (ZHX)-1-interacting proteins: molecular cloning and characterization of a member of the ZHX family, ZHX3.

Human zinc-fingers and homeoboxes (ZHX) 1, a transcriptional repressor, was originally cloned as an interacting protein with the activation domain of the A subunit of nuclear factor-Y (NF-YA). As the first step in investigating the mechanism by which ZHX1 acts as a transcriptional repressor, we conducted a search of ZHX1-interacting proteins using a yeast two-hybrid system. Nuclear proteins such as ZHX1, transcriptional co-factors and DNA-binding proteins, zyxin, androgen-induced aldose reductase and eleven-nineteen lysine-rich leukaemia gene, as well as some unknown proteins, were cloned. Molecular cloning and determination of the nucleotide sequence of the full-length cDNA encoding a novel protein revealed that it consists of 956 amino acid residues and contains two zinc-finger (Znf) motifs and five homeodomains (HDs) as well as ZHX1. We concluded that the protein forms the ZHX family with ZHX1 and denoted it ZHX3. ZHX3 not only dimerizes with both ZHX1 and ZHX3, but also interacts with the activation domain of the NF-YA. Further analysis revealed that ZHX3 is a ubiquitous transcriptional repressor that is localized in nuclei and functions as a dimer. Lastly, the dimerization domain, the interaction domain with NF-YA, and the repressor domain are mapped to a region including the HD1 region, and two nuclear localization signals are mapped to the N-terminal through Znf1 and the HD2 region, respectively.

Genomic structure and analysis of transcriptional regulation of the mouse zinc-fingers and homeoboxes 1 (ZHX1) gene.

The mouse zinc-fingers and homeoboxes 1 (ZHX1) gene was cloned and its transcriptional regulatory mechanism analysed. The mouse ZHX1 gene spans approximately 29 kb and consists of five exons. Exons 1-3 contain the nucleotide sequence of the 5'-noncoding region of mouse ZHX1 cDNA, exon 4 contains a part of the 5'-noncoding region, an entire coding sequence, and a part of the 3'-noncoding sequence, and exon 5 contains the resulting 3'-noncoding sequence. The ZHX1 gene exists as one copy in the haploid mouse genome. Two species of ZHX1 mRNA with or without the nucleotide sequence of the third exon are produced by an alternative splicing. To investigate the regulatory elements involved in the transcription of the ZHX1 gene, transient DNA transfection experiments with ZHX1/firefly luciferase reporter genes were performed using a lipofection method. Functional analyses of a series of 5'- and 3'-deletion constructs of the reporter genes revealed that the nucleotide sequence between -59 and +50 is required for full promoter activity in mouse embryonal carcinoma F9 cells. Two positive regulatory cis-acting elements in the region were identified. These elements, designated as Box A and Box B, are located between nucleotides -47 and -42 and +22 and +27, respectively, and synergistically stimulate transcription of the mouse ZHX1 gene. Electrophoretic mobility shift assays with specific competitors and antibodies show that PEA3 and Yin and Yang 1 (YY1) bind to Box A and Box B, respectively. Thus, we conclude that PEA3 and YY1 synergistically stimulate the transcription of the ZHX1 gene.

Functional analysis and the molecular dissection of zinc-fingers and homeoboxes 1 (ZHX1).

Zinc-fingers and homeoboxes 1 (ZHX1) is a protein that interacts with the activation domain of the A subunit of nuclear factor-Y. The function of ZHX1, as a transcription factor, was characterized and their domains were mapped. To determine the nuclear localization signal, expression vectors, in which various truncated forms of ZHX1 were fused to the C-terminal of green fluorescence protein (GFP), were transfected into human embryonic kidney (HEK) 293 cells. All GFP-ZHX1 fusion proteins including an arginine-rich region that corresponds to the amino acid sequence between 734 and 768 were localized in the nuclei. A dimerization domain of the ZHX1 was also mapped using protein-protein interaction assays. The homeodomain (HD) 1 consisting of the amino acid sequence between 272 and 432 of ZHX1 was necessary and sufficient for dimerization. Lastly, the transcriptional activity of ZHX1 was examined using a mammalian one-hybrid system. ZHX1, fused to the C-terminal of the GAL4 DNA-binding domain, was co-transfected with luciferase reporter plasmids with or without five copies of the GAL4-binding site into HEK293 cells. The luciferase activity was decreased in both concentration- and GAL4-binding site-dependent manner. The acidic region corresponding to the amino acid sequence between 831 and 873 was a repressor domain and dimerization was prerequisited for full repressor activity.

Unexpectedly high prevalence of the mild form of propionic acidemia in Japan: presence of a common mutation and possible clinical implications.

Propionic acidemia [MIM 606054] is a form of organic acidemia caused by genetic deficiency of propionyl-CoA carboxylase (PCC) and characterized by attacks of severe metabolic acidemia and hyperammonemia beginning in the neonatal period or in early infancy. There are, however, patients who have higher PCC activities and present later with unusual symptoms, such as mild mental retardation or extrapyramidal symptoms, sometimes even without metabolic acidosis. Through the neonatal screening of more than 130,000 Japanese newborns we detected a frequency of patients with propionic acidemia more than ten times higher than previously reported, most of them with milder phenotypes. The mutational spectrum was quite different from that of patients with the severe form and there was a common mutation (Y435C) in the beta subunit of the PCC gene (PCCB). Since patients with the mild form could present with unusual symptoms and therefore could easily remain unrecognized, it is important to identify those patients and clarify their natural history. Molecularly, one of the mutations (A1288C) caused an unusual pattern of multiple exon skipping and another unidentified mutation lead to the absence of mRNA. Taking into consideration previous findings regarding PCCB mutations, it appears that this gene is particularly prone to posttranscriptional modifications such as missense mediated exon skipping, mRNA decay, or rapid product degradation.

Newborn mass screening and selective screening using electrospray tandem mass spectrometry in Japan.

Electrospray tandem mass spectrometry was applied to detect a series of inherited metabolic disorders during a newborn-screening pilot study and a selective screening in Japan. In our mass screening of 102,200 newborns, five patients with propionic acidemia, two with methylmalonic acidemia, two with medium-chain acyl-CoA dehydrogenase deficiency, three with citrullinemia type II, and one with phenylketonuria were identified. In a selective screening of 164 patients with symptoms mainly related to hypoglycemia and/or hyperammonemia, 12 with fatty acid oxidation disorders and six with other disorders were found. The results indicated the importance of newborn screening using this technology in Japan.

Rat zinc-fingers and homeoboxes 1 (ZHX1), a nuclear factor-YA-interacting nuclear protein, forms a homodimer.

Zinc-fingers and homeoboxes 1 (ZHX1) is a protein which interacts with the activation domain of the A subunit of nuclear factor-Y. To analyze the physiological role(s) of ZHX1, we searched ZHX1-interacting protein(s) using a yeast two-hybrid system. The rat counterpart of ZHX1 cDNAs was cloned from an ovarian granulosa cell complementary DNA (cDNA) library, indicating that ZHX1 is able to form a homodimer. An analysis of the nucleotide sequence and its deduced amino acid sequence show that rat ZHX1 consists of 873 amino acid residues. Northern blot analysis shows that ZHX1 messenger RNA is expressed ubiquitously and that the level in the ovary are not regulated by gonadotropins. Furthermore, transfection experiments with green fluorescence protein (GFP) expression vectors into human embryonic kidney HEK293 cells reveal that full-length ZHX1 fused to the GFP is localized in the nuclei. Thus, we report on the molecular cloning, expression and characterization of full-length rat ZHX1 cDNA.