Usefulness of the Fibrosis-4 index and alanine aminotransferase at 1 year of nucleos(t)ide analog treatment for prediction of hepatocellular carcinoma in chronic hepatitis B patients.

AIM: Nucleos(t)ide analogs do not completely prevent hepatocellular carcinoma (HCC) in chronic hepatitis B virus infection. This study aimed to evaluate the dynamics of a non-invasive liver fibrosis marker, the Fibrosis-4 (FIB-4) index, for predicting HCC development. METHODS: Among a total of 882 chronically hepatitis B virus infection-infected patients who were treated with nucleos(t)ide analogs, 472 patients without HCC history whose FIB-4 at baseline and 1 year of treatment was obtained were evaluated for the incidence of HCC. RESULTS: The median FIB-4 was 2.00 at baseline and was significantly reduced to 1.58 at 1 year (P < 0.001), but the reduction was small at 2 years or later. When a receiver operating characteristic analysis of FIB-4 was performed to predict HCC within 5 years, the area under the curve of FIB-4 at 1 year was higher than that at baseline (0.676 vs. 0.599). The HCC incidence was significantly higher in patients with FIB-4 ≥1.58 than in those with FIB-4 <1.58 (14.8% vs. 3.6% at 10 years, P < 0.001). Additionally, an abnormal alanine aminotransferase (≥31 U/L) at 1 year was an independent risk for HCC. When a fibrosis and alanine aminotransferase-1 (FAL-1) score was evaluated as an applicable number of FIB-4 ≥1.58, and alanine aminotransferase ≥31 as 0, 1, and 2, the HCC risk in patients with score 2 was significantly higher than in those with score 1 or score 0 (24.1% vs. 9.8% vs. 0.7% at 10 years, P < 0.001). CONCLUSIONS: FIB-4 ≥1.58 and alanine aminotransferase ≥31 at 1 year of nucleos(t)ide analog was an independent risk factor for HCC development, and a score using these factors stratified the risk of HCC.

CD98 expression can be a predictive factor of resistance to radiotherapy in head and neck squamous cell carcinoma.

CD98 is a marker of cancer stem cells, and it regulates radiosensitivity in head and neck squamous cell carcinoma (HNSCC). The current study aimed to investigate whether CD98 can be used as a prognostic factor and marker of radioresistance. CD98 immunostaining was performed using biopsy specimens collected from patients diagnosed with HNSCC. The average period of postoperative monitoring was 31.6 months. The treatment options were radiation therapy with either cisplatin or cetuximab, and surgery. The participants were divided into groups of low and high fluorescence intensity. CD98 was an independent prognostic factor of radioresistance. In total, 103 patients were treated with chemoradiotherapy or bioradiotherapy. The overall survival rates of patients receiving chemoradiotherapy or bioradiotherapy were 69.2% in the low group and 36.2% in the high group. The progression-free survival rates were 60.0% and 24.6%, respectively. CD98 expression was considered an independent prognostic factor of overall survival and progression-free survival. In total, 99 patients underwent surgical treatment. The surgery group did not differ according to CD98 expression. Via CD98 immunostaining, sensitivity to radiotherapy can be determined in advance. In HNSCC, knowledge about sensitivity to radiotherapy can significantly improve prognosis.

Beneficial Effects of Low-Intensity Pulsed Ultrasound Therapy on Right Ventricular Dysfunction in Animal Models.

Right ventricular failure (RVF) is a leading cause of death in patients with pulmonary hypertension; however, effective treatment remains to be developed. We have developed low-intensity pulsed ultrasound therapy for cardiovascular diseases. In this study, we demonstrated that the expression of endothelial nitric oxide synthase (eNOS) in RVF patients was downregulated and that eNOS expression and its downstream pathway were ameliorated through eNOS activation in 2 animal models of RVF. These results indicate that eNOS is an important therapeutic target of RVF, for which low-intensity pulsed ultrasound therapy is a promising therapy for patients with RVF.

LAT1 is associated with poor prognosis and radioresistance in head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) has been identified as the sixth most common disease in the world, and its prognosis remains poor. The basic treatment of HNSCC includes a combination of chemoradiation and surgery. With the advent of immune checkpoint inhibitors, the prognosis has improved; however, the efficacy of checkpoint inhibitors is limited. L-type amino acid transporter 1 (LAT1), an amino acid transporter, is highly expressed in a cancer-specific manner. However, to the best of our knowledge, LAT1 expression in HNSCC has not been determined. Therefore, the present study aimed to examine the role of LAT1 expression in HNSCC. A total of three HNSCC cell lines (Sa3, HSC2 and HSC4) were used to investigate the characteristics of LAT1-positive cells, including their ability to form spheroids, and their invasion and migration. The present study also examined LAT1 by immunostaining of biopsy specimens from 174 patients diagnosed, treated and followed-up at Akita University (Akita, Japan) between January 2010 and December 2019, and overall survival, progression-free survival and multivariate analyses were performed. The results demonstrated that LAT1-positive cells in HNSCC were an independent prognostic factor for overall survival and progression-free survival, and were resistant to chemoradiation. Therefore, JPH203, a LAT1 inhibitor, may be effective in treating chemoradiotherapy-resistant HNSCC and may improve the prognosis of patients with HNSCC.

Mitochondrial connexin43 and mitochondrial KATP channels modulate triggered arrhythmias in mouse ventricular muscle.

Connexin43 (Cx43) exits as hemichannels in the inner mitochondrial membrane. We examined how mitochondrial Cx43 and mitochondrial KATP channels affect the occurrence of triggered arrhythmias. To generate cardiac-specific Cx43-deficient (cCx43-/-) mice, Cx43flox/flox mice were crossed with α-MHC (Myh6)-cre+/- mice. The resulting offspring, Cx43flox/flox/Myh6-cre+/- mice (cCx43-/- mice) and their littermates (cCx43+/+ mice), were used. Trabeculae were dissected from the right ventricles of mouse hearts. Cardiomyocytes were enzymatically isolated from the ventricles of mouse hearts. Force was measured with a strain gauge in trabeculae (22°C). To assess arrhythmia susceptibility, the minimal extracellular Ca2+ concentration ([Ca2+]o,min), at which arrhythmias were induced by electrical stimulation, was determined in trabeculae. ROS production was estimated with 2',7'-dichlorofluorescein (DCF), mitochondrial membrane potential with tetramethylrhodamine methyl ester (TMRM), and Ca2+ spark frequency with fluo-4 and confocal microscopy in cardiomyocytes. ROS production within the mitochondria was estimated with MitoSoxRed and mitochondrial Ca2+ with rhod-2 in trabeculae. Diazoxide was used to activate mitochondrial KATP. Most of cCx43-/- mice died suddenly within 8 weeks. Cx43 was present in the inner mitochondrial membrane in cCx43+/+ mice but not in cCx43-/- mice. In cCx43-/- mice, the [Ca2+]o,min was lower, and Ca2+ spark frequency, the slope of DCF fluorescence intensity, MitoSoxRed fluorescence, and rhod-2 fluorescence were higher. TMRM fluorescence was more decreased in cCx43-/- mice. Most of these changes were suppressed by diazoxide. In addition, in cCx43-/- mice, antioxidant peptide SS-31 and N-acetyl-L-cysteine increased the [Ca2+]o,min. These results suggest that Cx43 deficiency activates Ca2+ leak from the SR, probably due to depolarization of mitochondrial membrane potential, an increase in mitochondrial Ca2+, and an increase in ROS production, thereby causing triggered arrhythmias, and that Cx43 hemichannel deficiency may be compensated by activation of mitochondrial KATP channels in mouse hearts.

A Follow-up Report on the Diagnosis of Gastrointestinal Cancer during the COVID-19 Pandemic in Akita Prefecture, Japan in 2021.

We recently reported the decrease in the number of gastrointestinal (GI) cancer diagnoses in 2020 due to disturbance of the healthcare system by the coronavirus disease 2019 (COVID-19) pandemic, using a hospital-based cancer registration system in Akita prefecture, Japan. In this study, we extended the research by showing the latest data (2021) on the number of cancers and examinations. Information on the occurrence and stage of esophageal, gastric, and colorectal cancers was collected from the same database. The number of GI examinations (cancer screening procedures and endoscopic examinations) was also investigated. Following the immediate decrease in the numbers of both GI examinations and GI cancer diagnoses in 2020, a rebound increase in the numbers of GI cancer diagnoses-especially colorectal cancers-was observed in 2021, resulting from an increased number of GI examinations i.e., the total number of colorectal cancers in 2021 increased by 9.0% and 6.8% in comparison to 2020 and pre-pandemic era, respectively. However, the rebound increase in 2021 was largely due to an increase in early-stage cancers, and there was no apparent trend toward the increased predominance of more advanced cancers. It therefore seems that we managed to escape from the worst-case scenario of disturbance of the healthcare system due to pandemic (i.e., an increase in the number of more advanced cancers due to delayed diagnoses). We need to continue to watch the trends in Akita prefecture, which has the highest rate of mortality from the 3 major GI cancers in Japan.

Case Report: Anti-mGluR5 antibody-negative Ophelia syndrome with failed lymph node biopsy due to steroid therapy.

Ophelia syndrome is paraneoplastic limbic encephalitis (PLE) with Hodgkin lymphoma. Some Ophelia syndrome patients have been reported as testing positive for anti-metabotropic glutamate receptor 5 (mGluR5) antibodies. However, we experienced a case of anti-mGluR5 antibody-negative Ophelia syndrome. The type of onset, neurological symptoms, and imaging as well as electroencephalographic findings were like previous reports except for a normal cell count in cerebrospinal fluid (CSF). Unfortunately, a lymph node biopsy failed and could not diagnose the patient before death because steroid treatment for limbic encephalitis had shrunk lymph nodes. We believe it is essential to accumulate cases of this syndrome and clarify the association between PLE and Hodgkin lymphoma so chemotherapy can be initiated even if malignant lymphoma cannot be pathologically proven or when antibodies cannot be measured or are negative.

GPNMB-Positive Cells in Head and Neck Squamous Cell Carcinoma-Their Roles in Cancer Stemness, Therapy Resistance, and Metastasis.

Objective: Despite the use of surgical and chemoradiation therapies, head and neck squamous cell carcinoma (HNSCC) still has a poor prognosis. Immune checkpoint inhibitors have been shown to prolong life expectancy but have limited efficacy. Glycoprotein nonmetastatic melanoma protein B (GPNMB) has received significant attention in breast cancer treatment, in which it has been associated with cancer stem cells (CSCs) and epithelial-mesenchymal transition (EMT); however, the function of GPNMB in HNSCC is completely unknown. This study aimed to clarify the characteristics of GPNMB-positive cells in vitro and their association with the prognosis by immunostaining clinical specimens. Methods: We examined the sphere formation, invasion, and migration ability of GPNMB-positive cells in four HNSCC cell lines in vitro. We also immunostained biopsy specimens with GPNMB from 174 patients with HNSCC diagnosed, treated, and followed-up in our institution to evaluate overall survival and progression-free survival. Results: GPNMB-positive cells showed enhanced sphere formation, invasion, and migration, suggesting that they could have CSC characteristics and the ability to induce EMT, as reported for breast cancer. Clinical specimens showed that overall survival was 39.4% and 57.8% (p = 0.045) and that progression-free survival was 27.6% and 51.6% (p = 0.013) for the high-expression and the low-expression groups, respectively, indicating poor prognosis for the high GPNMB group. The high GPNMB group was also more resistant to chemoradiation and bioradiotherapy. GPNMB was more highly expressed in metastatic lymph nodes than in the primary tumor. Conclusion: GPNMB-positive cells might have CSC characteristics and induce EMT. Detailed functional analyses of GPNMB in HNSCC and the establishment of therapies targeting GPNMB will lead to improved prognoses.

Non-Achievement of Alanine Aminotransferase Normalization Associated with the Risk of Hepatocellular Carcinoma during Nucleos(t)ide Analogue Therapies: A Multicenter Retrospective Study.

Patients with a chronic hepatitis B virus (HBV) infection who are treated with nucleos(t)ide analogues (NAs) are still at risk for hepatocellular carcinoma (HCC), and it has been clinically questioned whether patients with a high risk of HCC can be identified efficiently. We aimed to clarify the risk factors associated with the development of HCC during NA therapies. A total of 611 chronically HBV-infected patients without a history of HCC, who were treated with NAs for more than 6 months (median 72 months), from 2000 to 2021, were included from 16 hospitals in the Tohoku district in Japan. Incidences of HCC occurrence were analyzed with clinical factors, including on-treatment responses. Alanine aminotransferase (ALT) normalization, based on the criteria of three guidelines, was analyzed with other parameters, including the age−male−ALBI−platelets (aMAP) risk score. During the observation period, 48 patients developed HCC, and the cumulative HCC incidence was 10.6% at 10 years. Non-achievement of ALT normalization at 1 year of therapy was mostly associated with HCC development when ALT ≤ 30 U/L was used as the cut-off (cumulative incidence, 19.9% vs. 5.3% at 10 years, p < 0.001). The effectiveness of the aMAP risk score at the start of treatment was validated in this cohort. A combination of an aMAP risk score ≥ 50 and non-achievement of ALT normalization could stratify the risk of HCC significantly, and notably, there was no HCC development in 103 patients without these 2 factors. In conclusion, non-achievement of ALT normalization (≤30 U/L) at 1 year might be useful in predicting HCC during NA therapies and, in combination with the aMAP risk score, could stratify the risk more precisely.

Tumor Infiltrating Lymphocytes are Prognostic Factors and Can Be Markers of Sensitivity to Chemoradiotherapy in Head and Neck Squamous Cell Carcinoma.

BACKGROUND: Tumor-infiltrating lymphocytes (TILs) are assessed by the ratio of the area of lymphocytes infiltrating the stroma. TILs are important in breast cancer and malignant melanoma and are being established as a marker of prognosis and sensitivity to chemotherapy. This has resulted in various therapies being developed in fields such as breast cancer. However, the evaluation of TILs in head and neck squamous cell carcinoma (HNSCC) is not progressing, and the prognosis is still poor. Thus, investigating whether or not the evaluation of TILs is also effective in HNSCC and prognoses can be predicted with just biopsy samples alone is required. METHODS: This study included 153 patients who were diagnosed with HNSCC between January 2010 and December 2019, underwent treatment, and could be followed up thereafter at our institution. RESULTS: TILs, overall survival (OS), and progression-free survival (PFS) were evaluated in all patients, the chemoradiotherapy arm, and the surgery arm. The cut-off value for TILs was 50%. In all patients, OS was 69.8% and 40.2% (P = 0.01) and PFS was 58.4% and 31.6% (P = 0.003) in the high and low TIL groups, respectively. Multivariate analyses revealed that TILs independently predicted prognosis. In the chemoradiotherapy arm, OS was 70.8% and 31.6% (P = 0.012) and PFS was 63.4% and 20.3% (P = 0.001) in the high and low TIL groups, respectively. No significant differences were noted in the surgery arm. CONCLUSIONS: In HNSCC, TILs can be used as a prognosis predictor and chemoradiotherapy biomarker. Assessments can be performed just with hematoxylin-eosin staining and is very simple. This will greatly contribute to report personalized therapy progress. Further evaluations and, thus, prospective clinical multicenter trials are needed to use TILs in clinical practice for HNSCC.

Disturbance of Gastrointestinal Cancers Diagnoses by the COVID-19 Pandemic in a Depopulated Area of Japan: A Population-Based Study in Akita Prefecture.

Disruption of cancer screening programs and diagnoses of gastrointestinal cancers by the COVID-19 pandemic has been reported; however, little attention has been paid to the situation in depopulated areas with low infection rates. Akita Prefecture is one of the most depopulated areas of Japan and has the lowest COVID-19 infection rate per capita; at the same time, the prefecture has been top-ranked for mortality due to gastrointestinal cancer for years. In this population-based study in Akita Prefecture, we investigated the occurrence of gastrointestinal cancers and the number of cancer screening procedures over the five-year period of 2016-2020, employing a database from the collaborative Akita Prefecture hospital-based registration system of cancers. The occurrence of gastrointestinal cancers, especially esophago-gastric cancers, declined by 11.0% in 2020, when the COVID-19 pandemic affected the overall healthcare system, compared with the average of 2016-2019. Nonetheless, the occurrence of advanced-stage (stage IV) esophago-gastric cancers increased by 7.2% in 2020. The decrease in the gastrointestinal cancer diagnosis rate in 2020 coincided with a 30% decline in the total number of regular population-based screening programs. Under the ongoing COVID-19 pandemic, cancer screening was uniformly suspended throughout Japan. Accordingly, the COVID-19 pandemic has substantially disrupted the cancer screening system, leading to delays in diagnoses of gastrointestinal cancer, even in depopulated areas (Akita Prefecture) of Japan with a low prevalence of infection. Suspension of cancer screening procedures during an infectious disease pandemic should be thoroughly considered for each region based on the cancer incidence and infection status in that area.

Roles of stretch-activated channels and NADPH oxidase 2 in the induction of twitch contraction by muscle stretching in rat ventricular muscle.

Mechano-electric feedback means that muscle stretching causes depolarization of membrane potential. We investigated whether muscle stretching induces action potential and twitch contraction with a threshold of sarcomere length (SL) and what roles stretch-activated channels (SACs) and stretch-activated NADPH oxidase (X-ROS signaling) play in the induction. Trabeculae were obtained from the right ventricles of rat hearts. Force, SL, and [Ca2+]i were measured. Various degrees of stretching from the SL of 2.0 µm were applied 0.5 s after the last stimulus of the electrical train with 0.4-s intervals for 7.5 s. The SLtwitch was defined as the minimal SL at which twitch contraction was induced by the stretching. Muscle stretching induced twitch contraction with a threshold of SL at 0.4-s stimulus intervals ([Ca2+]o = 0.7 mmol/L). The SLtwitch was not changed by increasing the stimulus intervals and [Ca2+]o and by adding 1 µmol/L isoproterenol. The SLtwitch was not changed by adding 10 µmol/L Gd3+, 100 µmol/L or 200 µmol/L streptomycin, and 5 µmol/L GsMTx4. The SLtwitch was not changed by adding 1 µmol/L ryanodine and 3 µmol/L diphenyleneiodonium chloride. In contrast, the SLtwitch was increased by elevating extracellular K+ from 5 to 10 mmol/L and by adding the stretching during the refractory period of membrane potential. The addition of the stretching-induced twitch contraction more frequently induced arrhythmias. These results suggest that muscle stretching can induce twitch contraction with a threshold of SL and concern the occurrence of arrhythmias and that SACs and X-ROS signaling play no roles in the induction.

Effect of transient elevation of glucose on contractile properties in non-diabetic rat cardiac muscle.

In non-diabetic patients with severe disease, such as acute myocardial infarction or acute heart failure, admission blood glucose level is associated with their short-term and long-term mortality. We examined whether transient elevation of glucose affects contractile properties in non-diabetic hearts. Force, intracellular Ca2+ ([Ca2+]i), and sarcomere length were measured in trabeculae from rat hearts. To assess contractile properties, maximum velocity of contraction (Max dF/dt) and minimum velocity of relaxation (Min dF/dt) were calculated. The ratio of phosphorylated troponin I (P-TnI) to troponin I (TnI) was measured. One hour after elevation of glucose from 150 to 400 mg/dL, developed force, Max dF/dt, and Min dF/dt were reduced without changes in [Ca2+]i transients at 2.5 Hz stimulation and 2.0 mM [Ca2+]o, while developed force and [Ca2+]i transients showed no changes at 0.5 Hz stimulation and 0.7 mM [Ca2+]o. In the presence of 1 µM KN-93, a Ca2+/calmodulin-dependent protein kinaseII (CaMKII) inhibitor, or 50 µM diazo-5-oxonorleucine, a L-glutamine-D-fructose-6-phosphate amidotransferase inhibitor, the reduction of contractile properties after elevation of glucose was suppressed. Furthermore, 1 h after elevation of glucose to 400 mg/dL at 2.0 mM [Ca2+]o, the ratio of P-TnI to TnI was increased. These results suggest that in non-diabetic hearts under higher Ca2+-load, transient elevation of glucose for 1 h reduces contractile properties probably by activating CaMKII through O-GlcNAcylation. Thus, in the patients with severe disease, transient elevation of blood glucose, such as due to stress, may worsen cardiac function and thereby affect their mortality without known diabetes.

Low-intensity pulsed ultrasound ameliorates cardiac diastolic dysfunction in mice: a possible novel therapy for heart failure with preserved left ventricular ejection fraction.

AIMS: Heart failure with preserved left ventricular ejection fraction (HFpEF) is a serious health problem worldwide, as no effective therapy is yet available. We have previously demonstrated that our low-intensity pulsed ultrasound (LIPUS) therapy is effective and safe for angina and dementia. In this study, we aimed to examine whether the LIPUS therapy also ameliorates cardiac diastolic dysfunction in mice. METHODS AND RESULTS: Twelve-week-old obese diabetic mice (db/db) and their control littermates (db/+) were treated with either the LIPUS therapy [1.875 MHz, 32 cycles, Ispta (spatial peak temporal average intensity) 117-162 mW/cm2, 0.25 W/cm2] or placebo procedure two times a week for 4 weeks. At 20-week-old, transthoracic echocardiography and invasive haemodynamic analysis showed that cardiac diastolic function parameters, such as e', E/e', end-diastolic pressure-volume relationship, Tau, and dP/dt min, were all deteriorated in placebo-treated db/db mice compared with db/+ mice, while systolic function was preserved. Importantly, these cardiac diastolic function parameters were significantly ameliorated in the LIPUS-treated db/db mice. We also measured the force (F) and intracellular Ca2+ ([Ca2+]i) in trabeculae dissected from ventricles. We found that relaxation time and [Ca2+]i decay (Tau) were prolonged during electrically stimulated twitch contractions in db/db mice, both of which were significantly ameliorated in the LIPUS-treated db/db mice, indicating that the LIPUS therapy also improves relaxation properties at tissue level. Functionally, exercise capacity was also improved in the LIPUS-treated db/db mice. Histologically, db/db mice displayed progressed cardiomyocyte hypertrophy and myocardial interstitial fibrosis, while those changes were significantly suppressed in the LIPUS-treated db/db mice. Mechanistically, western blot showed that the endothelial nitric oxide synthase (eNOS)-nitric oxide (NO)-cGMP-protein kinase G (PKG) pathway and Ca2+-handling molecules were up-regulated in the LIPUS-treated heart. CONCLUSIONS: These results indicate that the LIPUS therapy ameliorates cardiac diastolic dysfunction in db/db mice through improvement of eNOS-NO-cGMP-PKG pathway and cardiomyocyte Ca2+-handling system, suggesting its potential usefulness for the treatment of HFpEF patients.

CD7-Positive Diffuse Large B-Cell Lymphoma Presenting as an Intranasal Tumor.

We report a case of a 74-year-old man with a cluster of differentiation (CD) 7-positive diffuse large B-cell lymphoma (DLBCL) in the right nasal cavity. Flow cytometry analyses showed CD7 and CD20 positivity in tumor cells. The patient received 6 cycles of R-CHOP plus local radiation therapy because positron emission tomography-computed tomography after R-CHOP revealed an intranasal lesion. The patient achieved complete remission (CR) after radiation therapy. The frequency of CD7-positive DLBCL is rare, and only 11 cases with follow-up of clinical course have been reported thus far. CR or partial response was noted in 8 of 11 cases after receiving rituximab combined with chemotherapy. In total, 9 of 12 cases involved the development of extranodal lesions, which occurred as an intranasal tumor in 3 cases. It is important to examine the clinical features by accumulation of further cases.

Transient Elevation of Glucose Increases Arrhythmia Susceptibility in Non-Diabetic Rat Trabeculae With Non-Uniform Contraction.

BACKGROUND: In non-diabetic patients with acute coronary syndrome, stress hyperglycemia occasionally occurs and is related to their mortality. Whether transient elevation of glucose affects arrhythmia susceptibility in non-diabetic hearts with non-uniform contraction was examined.Methods and Results:Force, intracellular Ca2+([Ca2+]i), and membrane potential were measured in trabeculae from rat hearts. Non-uniform contraction was produced by a jet of paralyzing solution. Ca2+waves and arrhythmias were induced by electrical stimulation (2.0 mmol/L [Ca2+]o). The activity of Ca2+/calmodulin-dependent protein kinaseII (CaMKII) was measured. An elevation of glucose from 150 to 400 mg/dL increased the velocity of Ca2+waves and the number of spontaneous action potentials triggered by electrical stimulation. Besides, the elevation of glucose increased the CaMKII activity. In the presence of 1 µmol/L KN-93, the elevation of glucose did not increase the velocity of Ca2+waves and the number of triggered action potentials. In addition, in the presence of 1 µmol/L autocamtide-2 related inhibitory peptide or 50 µmol/L diazo-5-oxonorleucine, the elevation of glucose did not increase the number of triggered action potentials. Furthermore, the elevation of glucose by adding L-glucose did not increase their number. CONCLUSIONS: In non-diabetic hearts with non-uniform contraction, transient elevation of glucose increases the velocity of Ca2+waves by activating CaMKII,probably through glycosylation with O-linked ß-N-acetylglucosamine, thereby increasing arrhythmia susceptibility.

Mechano-electric and mechano-chemo-transduction in cardiomyocytes.

Cardiac excitation-contraction (E-C) coupling is influenced by (at least) three dynamic systems that couple and feedback to one another (see Abstract Figure). Here we review the mechanical effects on cardiomyocytes that include mechano-electro-transduction (commonly referred to as mechano-electric coupling, MEC) and mechano-chemo-transduction (MCT) mechanisms at cell and molecular levels which couple to Ca2+ -electro and E-C coupling reviewed elsewhere. These feedback loops from muscle contraction and mechano-transduction to the Ca2+ homeodynamics and to the electrical excitation are essential for understanding the E-C coupling dynamic system and arrhythmogenesis in mechanically loaded hearts. This white paper comprises two parts, each reflecting key aspects from the 2018 UC Davis symposium: MEC (how mechanical load influences electrical dynamics) and MCT (how mechanical load alters cell signalling and Ca2+ dynamics). Of course, such separation is artificial since Ca2+ dynamics profoundly affect ion channels and electrogenic transporters and vice versa. In time, these dynamic systems and their interactions must become fully integrated, and that should be a goal for a comprehensive understanding of how mechanical load influences cell signalling, Ca2+ homeodynamics and electrical dynamics. In this white paper we emphasize current understanding, consensus, controversies and the pressing issues for future investigations. Space constraints make it impossible to cover all relevant articles in the field, so we will focus on the topics discussed at the symposium.

Anti-drug Antibodies Against a Novel Humanized Anti-CD20 Antibody Impair Its Therapeutic Effect on Primary Biliary Cholangitis in Human CD20- and FcγR-Expressing Mice.

There is considerable interest in expanding B cell-targeted therapies in human autoimmune diseases. However, clinical trials in human primary biliary cholangitis (PBC) using a chimeric antibody against human CD20 (hCD20) have showed limited efficacy. Two potential explanations for these disappointing results are the appearance of anti-drug antibodies (ADAs) and the high frequency of patients with moderate PBC or patients who had failed ursodeoxycholic acid treatment. Here, we studied a novel humanized IgG1 antibody against hCD20 and explored its efficacy in early stage PBC using a well-defined murine model. We developed a unique murine model consisting of dnTGF-ßRII mice expressing hCD20 and human Fcγ receptors (hFcγRs). Beginning at 4-6 weeks of age, equivalent to stage I/II human PBC, female mice were given weekly injections of an anti-hCD20 antibody (TKM-011) or vehicle control, and monitored for liver histology as well as a broad panel of immunological readouts. After 16 weeks' treatment, we observed a significant reduction in portal inflammation, a decrease in liver-infiltrating mononuclear cells as well as a reduction in liver CD8+ T cells. Importantly, direct correlations between numbers of liver non-B cells and B cells (r = 0.7426, p = 0.0006) and between numbers of liver memory CD8+ T cells and B cells (r = 0.6423, p = 0.0054) were apparent. Accompanying these changes was a dramatic reduction in anti-mitochondrial antibodies (AMAs), interleukin (IL)-12p40 and IL-5, and elevated levels of the anti-inflammatory chemokine CXCL1/KC. In mice that developed ADAs, clinical improvements were less pronounced. Sustained treatment with B cell-targeted therapies may broadly inhibit effector pathways in PBC, but may need to be administered early in the natural history of PBC.

Different roles of myocardial ROCK1 and ROCK2 in cardiac dysfunction and postcapillary pulmonary hypertension in mice.

Although postcapillary pulmonary hypertension (PH) is an important prognostic factor for patients with heart failure (HF), its pathogenesis remains to be fully elucidated. To elucidate the different roles of Rho-kinase isoforms, ROCK1 and ROCK2, in cardiomyocytes in response to chronic pressure overload, we performed transverse aortic constriction (TAC) in cardiac-specific ROCK1-deficient (cROCK1-/-) and ROCK2-deficient (cROCK2-/-) mice. Cardiomyocyte-specific ROCK1 deficiency promoted pressure-overload-induced cardiac dysfunction and postcapillary PH, whereas cardiomyocyte-specific ROCK2 deficiency showed opposite results. Histological analysis showed that pressure-overload-induced cardiac hypertrophy and fibrosis were enhanced in cROCK1-/- mice compared with controls, whereas cardiac hypertrophy was attenuated in cROCK2-/- mice after TAC. Consistently, the levels of oxidative stress were up-regulated in cROCK1-/- hearts and down-regulated in cROCK2-/- hearts compared with controls after TAC. Furthermore, cyclophilin A (CyPA) and basigin (Bsg), both of which augment oxidative stress, enhanced cardiac dysfunction and postcapillary PH in cROCK1-/- mice, whereas their expressions were significantly lower in cROCK2-/- mice. In clinical studies, plasma levels of CyPA were significantly increased in HF patients and were higher in patients with postcapillary PH compared with those without it. Finally, high-throughput screening demonstrated that celastrol, an antioxidant and antiinflammatory agent, reduced the expressions of CyPA and Bsg in the heart and the lung, ameliorating cardiac dysfunction and postcapillary PH induced by TAC. Thus, by differentially affecting CyPA and Bsg expressions, ROCK1 protects and ROCK2 jeopardizes the heart from pressure-overload HF with postcapillary PH, for which celastrol may be a promising agent.