The Hippo-YAP Signaling Pathway in Osteoarthritis and Rheumatoid Arthritis.

Arthritis is the most prevalent joint disease and is characterized by articular cartilage degradation, synovial inflammation, and changes in periarticular and subchondral bone. Recent studies have reported that Yes-associated protein (YAP) and the transcriptional coactivator with PDZ-binding motif (TAZ) have significant effects on the proliferation, migration, and survival of chondrocytes and fibroblast-like synovial cells (FLSs). YAP/TAZ signaling pathway, as well as the related Hippo-YAP signaling pathway, are responsible for the condition of cells and articular cartilage in joints. They are tightly regulated to maintain metabolism in chondrocytes and FLSs because abnormal expression may result in cartilage damage. However, the roles and mechanisms of the Hippo-YAP pathway in arthritis remain largely unknown. This review summarizes the roles and key functions of YAP/TAZ and the Hippo-YAP signaling pathway in FLSs and chondrocytes for the induction of proliferation, migration, survival, and differentiation in rheumatoid arthritis (RA) and osteoarthritis (OA) research. We also discuss the therapeutic strategies involving YAP/TAZ and the related Hippo-YAP signaling pathway involved in OA.

The Expression of αvß3 and Osteopontin in Osteoarthritic Knee Cartilage and Their Correlations With Disease Severity and Chondrocyte Senescence.

Osteoarthritis (OA) is the main joint disease associated with aging. Previous studies have confirmed that both osteopontin (OPN) and αvß3 integrin are involved in the progression of knee OA. The purpose of this study was to determine the expression of OPN and αvß3 integrin and chondrocyte senescence levels in OA. Forty-six cartilage tissues from normal and knee OA patients were divided into 4 groups of normal, minor, moderate, and severe lesions based on the Mankin score. Immunohistochemistry and western blotting were used to determine the expression of αvß3, OPN, and senescent-associated-ß-galactosidase (SAß-gal) in articular cartilage. Then, Spearman's correlation was used to analyze the correlations between the Mankin scores and αvß3, OPN and SAß-gal. Pearson correlation analysis was used to analyze the correlations among αvß3, OPN, and SAß-gal. The expression of OPN, αvß3, and SAß-gal in articular cartilage was explored. αvß3, OPN, and SAß-gal proteins were all elevated in OA cartilage, and the correlation coefficient between the Mankin score and the average optical density value of αvß3, OPN, SAß-gal were r =0.60, r =0.75, and r =0.87, respectively, all P <0.001; the correlation between the average optical density value of αvß3 and OPN was r =0.3191, P <0.05; the correlation between αvß3 and SAß-gal was r =0.4955, P <0.001; and the correlation between OPN and SAß-gal was r =0.7821, P <0.001. The correlations among αvß3, OPN, and SAß-gal expression in articular cartilage might be important in OA progression and pathogenesis. Nonetheless, more research is needed to elucidate the exact contribution of αvß3, OPN, and SAß-gal to the degenerative process of OA.

Osteopontin, a bridge links osteoarthritis and osteoporosis.

Osteoarthritis (OA) is the most prevalent joint disease characterized by degradation of articular cartilage, inflammation, and changes in periarticular and subchondral bone of joints. Osteoporosis (OP) is another systemic skeletal disease characterized by low bone mass and bone mineral density (BMD) accompanied by microarchitectural deterioration in bone tissue and increased bone fragility and fracture risk. Both OA and OP are mainly affected on the elderly people. Recent studies have shown that osteopontin (OPN) plays a vital role in bone metabolism and homeostasis. OPN involves these biological activities through participating in the proliferation, migration, differentiation, and adhesion of several bone-related cells, including chondrocytes, synoviocytes, osteoclasts, osteoblasts, and marrow mesenchymal stem cells (MSCs). OPN has been demonstrated to be closely related to the occurrence and development of many bone-related diseases, such as OA and OP. This review summarizes the role of OPN in regulating inflammation activity and bone metabolism in OA and OP. Furthermore, some drugs that targeted OPN to treat OA and OP are also summarized in the review. However, the complex mechanism of OPN in regulating OA and OP is not fully elucidated, which drives us to explore the depth effect of OPN on these two bone diseases.

Clinical Features of Aortic Dissection in the Emergency Department: A Single-center Experience from South China.

OBJECTIVES: Our goal in this study was to determine 1) whether there are any differences in clinical characteristics between Chinese and Western patients with aortic dissection (AD), and 2) the mortality rate of AD patients in the emergency department (ED) and identify the risk predictors for death. METHODS: We retrospectively analyzed patients who were diagnosed with AD and admitted to our ED between September 1, 2017-August 31, 2020. Data on age, gender, clinical manifestation, medical history, routine blood tests, liver and kidney function, coagulation, myocardial enzymology, and mortality were collected. RESULTS: We enrolled 535 AD patients (422 men and 113 women) with a mean age of 54.7±14.1 years. Type A AD constituted 40% of the total number of AD cases, while type B AD constituted 60%. The proportion of those who were females, 10-92 years, with type A AD, and hypertension in the Chinese population was lower than that in the Western population (P <0.05 for all). Type A AD patients had a higher proportion of acute AD clinical manifestations than did patients with type B AD (P = 0.0084, P <0.05). The mortality rate of type A AD patients (10.75%) was higher than that of type B AD patients (1.87%) (P <0.0001) in the ED. Higher values of white blood cells, neutrophils, high-density lipoprotein, activated partial thromboplastin time, and D-dimer level with worsened hepatic and renal function were found in the deceased group, and multivariate logistic regression revealed that blood urea nitrogen (BUN) levels (P = 0.0031, P <0.05) were significantly associated with death. CONCLUSION: In South China, patients with AD had a mean age of 54.7 years, with 78.88% prevalence in males and 66.92% hypertension rate. Type A AD accounted for 40% of all AD cases, and 10.70% of patients with type A AD died in the ED. Elevated BUN levels may be a risk predictor for death in patients with type A AD.

OPN inhibits autophagy through CD44, integrin and the MAPK pathway in osteoarthritic chondrocytes.

Background: To investigate whether osteopontin (OPN) affects autophagy in human osteoarthritic chondrocytes and determine the roles of CD44, αvß3 integrin and the Mitogen-activated protein kinase (MAPK) pathway in this progress. Methods: First, we compared the autophagy levels in the human osteoarthritis (OA) and normal cartilage, then, we cultured human OA chondrocytes in vitro and treated cells with recombinant human OPN (rhOPN) to determine autophagy changes. Next, the anti-CD44 and anti-CD51/61 monoclonal antibodies (Abs) or isotype IgG were used to determine the possible role of CD44 and αvß3 integrin; subsequently, an inhibitor of the ERK MAPK pathway was used to investigate the role of ERK MAPK. Western blotting was used to measure the Beclin1, LC3 II and MAPK proteins expressions, mRFP-GFP-LC3 confocal imaging and transmission electron microscopy were also used to detect the autophagy levels. Cell Counting Kit-8 (CCK-8) was used to assay the proliferation and activity of chondrocytes. Results: The LC3 protein was greatly decreased in OA cartilage compared to normal cartilage, and OPN suppressed the autophagy activity in chondrocytes in vitro. Blocking experiments with anti-CD44 and anti-CD51/61 Abs indicated that OPN could suppress the expression of LC3II and Beclin1 through αvß3 integrin and CD44. Our results also indicated that the ratio of p-ERK/ERK but not p-P38/P38 and p-JNK/JNK was increased after the rhOPN treatment. The ERK inhibitor inhibited the activity of OPN in the suppression of autophagy, and the CCK-8 results showed that rhOPN could promote chondrocyte proliferation. Conclusion: OPN inhibited chondrocyte autophagy through CD44 and αvß3 integrin receptors and via the ERK MAPK signaling pathway.

Caffeine alleviates acute liver injury by inducing the expression of NEDD4L and deceasing GRP78 level via ubiquitination.

BACKGROUND: Acute liver injury is liver cell injury that occurs rapidly in a short period of time. Caffeine has been shown to maintain hepatoprotective effect with an unclear mechanism. Endoplasmic reticulum stress (ERS) has significant effects in acute liver injury. Induction of GRP78 is a hallmark of ERS. Whether or not caffeine's function is related to GRP78 remains to be explored. METHODS: Acute liver injury model was established by LPS-treated L02 cells and in vivo administration of LPS/D-Gal in mice. Caffeine was pre-treated in L02 cells or mice. Gene levels was determined by real-time PCR and western blot. Cell viability was tested by CCK-8 assay and cell apoptosis was tested by flow cytometry. The interaction of GRP78 and NEDD4L was determined by Pull-down and co-immunoprecipitation (Co-IP) assay. The ubiquitination by NEDD4L on GRP78 was validated by in vitro ubiquitination assay. RESULTS: Caffeine protected liver cells against acute injury induced cell apoptosis and ERS both in vitro and in vivo. Suppression of GRP78 could block the LPS-induced cell apoptosis and ERS. NEDD4L was found to interact with GRP78 and ubiquitinate its lysine of 324 site directly. Caffeine treatment induced the expression of NEDD4L, resulting in the ubiquitination and inhibition of GRP78. CONCLUSION: Caffeine mitigated the acute liver injury by stimulating NEDD4L expression, which inhibited GRP78 expression via ubiquitination at its K324 site. Low dose of caffeine could be a promising therapeutic treatment for acute liver injury.

Risk Factors and Outcome Variables of Cardiorenal Syndrome Type 1 in Acute Myocardial Infarction Patients.

PURPOSE: This study's goal was to explore risk factors affecting short-term prognosis of cardiorenal syndrome type 1 (CRS1) in acute myocardial infarction (AMI) patients. METHODS: In this retrospective analysis of CRS1 in AMI patients hospitalized from January 2011 to December 2014, the patients were classified into deceased or survivor groups. Clinical data, including demographics, laboratory results, and 28-day outcomes, were collected. RESULTS: The incidence rate of CRS1 in AMI patients was 15.2% (274 in 1801). Ultimately, 88 patients were enrolled and 25 (28.4%) were classified into the deceased group, while 63 were classified into the survivor group. There were statistically significant differences between the groups for hypertension, mechanical ventilation, KIDGO stage, NT-proBNP, Hb, ALB, PCI, decreased LVEF, 7th-day SCr value, and the highest SCr value recorded within 7 days (all P < 0.05). Multivariate logistic regression showed that the following factors were significantly related to whether a patient died: requiring mechanical ventilation, increased NT-proBNP levels and 7th-day SCr values, and decreased LVEFs. The APACHE II, SOFA, and SASP II scores on the 7th day were significantly higher in the deceased group (all P < 0.05). The accuracy of APACHE II, SOFA, and SASP II scores on the 7th day for predicting death were 84.1%, 78.4% and 79.5%, respectively. The AUC of 7th-day APACHE II, SOFA, and SASP II scores was 0.844, 0.803, and 0.827, respectively, with no statistically significant differences between the three scores (P > 0.05). CONCLUSION: The mortality rate of CRS1 in AMI patients was 28.4% (25 in 88) within 28 days. Mechanical ventilation, increased NT-proBNP levels, the 7th-day SCr value, and decreased LVEF were related to death in AMI patients with CRS1. APACHE II, SOFA, and SAPS II scores on the 7th day were satisfactorily accurate in predicting death within 28 days.

Clinical Characteristics of Adult Hemophagocytic Lymphohistiocytosis in the Emergency Department.

PURPOSE: To determine the clinical manifestations and results of adult hemophagocytic lymphohistiocytosis (HLH) patients in our emergency department. METHODS: We retrospectively evaluated patients with HLH from 1 April 2018 to 31 December 2020. The clinical data of these patients (basic information, symptoms, vital signs, laboratory results, HLH diagnostic criteria, H Score, main treatments, outcomes) were collected. RESULTS: Thirty-three patients (23 males and 10 females; 40.55±18.78 years) with 34 clinical episodes (one male had two clinical episodes and died during the second episode) were enrolled. Twenty-five patients were placed in a "survivor" group, and nine patients were categorized into a "deceased" group. Fever, splenomegaly, hemoglobin <90 g/L and platelet count <100×109/L most commonly met the diagnostic standard for HLH. The H Score results in the survival group and deceased group was 212.4±37.18 and 252.1±40.95, respectively. Viral infection was the most common reason for HLH, followed by immune-system disease and cancer. Laboratory tests showed that deceased-group patients had multiple-organ dysfunction. Multivariate logistic regression showed that the lactate dehydrogenase (lactate dehydrogenase) level (P = 0.039; odds ratio, 0.999) was significantly related to death. CONCLUSION: In the emergency department, HLH should be considered for critically ill patients with fever, splenomegaly, low hemoglobin and low platelet count. The H Score might be useful to diagnose HLH quickly. In our study, 26.47% of HLH patients died in the emergency department, and patients with a significantly increased lactate dehydrogenase level had a markedly increased risk of death.

Therapeutical plasma exchange for thrombotic thrombocytopenic purpura in the emergency department: A single center experience.

INTRODUCTION: Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening and easily misdiagnosed thrombotic microangiopathy disease. Few studies have reported the use of therapeutic plasma exchange (TPE) for TTP in emergency departments in China. The present study was a retrospective analysis of patients with TTP who were treated with TPE in our emergency intensive care unit (EICU). METHODS: This study retrospectively analyzed patients with TTP who received TPE management from July 1, 2014 to February 1, 2020. The following clinical data of these patients were collected: laboratory results, first symptoms, ADAMTS13 levels, glucocorticoid levels, TPE times and outcomes. RESULTS: The study included 19 patients (9 male and 10 female) with 20 clinical episodes, and 1 female patient had two episodes. TPE was used in 17 patients, and TPE was performed once every 2-3 days in patients. The volume for each TPE treatment was 2000 ml. In total, 4 male patients died, and 15 patients survived. One female experienced a relapse. No significant differences in age, RBC, HGB, PLT, ALT, AST, BUN, Cr, LDH, or bilirubin were noted between the survival and death groups. The mortality rate of male patients was significantly higher than that of female patients(p = 0.0325, p < 0.05), and the mean age of deceased patients was 64.25 ± 4.78 years, which was older than the mean age of survivors (47.38 ± 4.30). However, no significant difference was noted (p = 0.0787). CONCLUSION: TPE had satisfactory results for TTP patients although it was not performed every day. Older male TTP patients exhibited a relatively increased risk of death.

The ß-catenin/TCF-4 pathway regulates the expression of OPN in human osteoarthritic chondrocytes.

BACKGROUND: Cartilage destruction is the main characteristic of osteoarthritis (OA), and osteopontin (OPN) is elevated in OA articular cartilage; however, the reason for the increased OPN level is not determined. In addition, Wnt/ß-catenin signaling participates in the progression of OA. The aim of the present study was to evaluate whether canonical Wnt signaling could regulate the expression of OPN in human chondrocytes in vitro. METHODS: Human chondrocytes were cultured in vitro, and we first assayed the mRNA levels of OPN and ß-catenin in chondrocytes. Next, we performed transient transfection of TCF 4 shRNA into chondrocytes to inhibit TCF 4 expression and explore changes in the OPN level. Then, the Wnt/ß-catenin signaling inhibitor Dickkopf-1 (Dkk-1) was incubated with chondrocytes, and we assayed the changes in ß-catenin and OPN. RESULTS: Our results showed that the expression of both ß-catenin and OPN was increased in OA chondrocytes, but there were no correlations between ß-catenin and OPN expression. TCF4 shRNA downregulated the expression of TCF 4 and OPN in chondrocytes, while after treatment with rDKK-1 at a concentration of 400 ng/ml for 24 h, the mRNA and protein expression of both ß-catenin and OPN was significantly decreased in chondrocytes. CONCLUSIONS: Elevated OPN expression might be regulated by the ß-catenin/TCF-4 pathway, and the Wnt/ß-catenin inhibitor DKK1 could inhibit the expression of ß-catenin and OPN in OA chondrocytes.

Effect of ulinastatin combined with mild therapeutic hypothermia on intestinal barrier dysfunction following cardiopulmonary resuscitation in rats.

The aim of the present study was to investigate the effect of ulinastatin (UTI) alone or combined with mild therapeutic hypothermia (MTH) on intestinal barrier dysfunction following cardiopulmonary resuscitation (CPR) in rats. A total of 25 adult male Sprague-Dawley rats were randomly organized into five groups: Sham; control; UTI; MTH; and the combined group. The latter four groups were induced with the asphyxiated cardiac arrest rat model and treated with different interventions. After 6 h of treatment, the intestinal tissues of the rats were examined by electron microscopy, and the levels of intestinal malondialdehyde (MDA) and superoxide dismutase (SOD) were determined. The results of the present study indicated that the target temperature had successfully been attained in MTH and the combined group, and the other three groups of rats all survived at a normal temperature. In the rats treated with UTI or MTH, the epithelial cells exhibited pathological changes in their tight junctions and epithelial cell surface microvilli compared with the sham group. In the rats treated with a combination of UTI and MTH, whilst the epithelial cells exhibited a few slight changes, including mitochondrial edema, they were largely similar to the normal epithelial cells. However, there were significant differences in the levels of MDA and SOD between the different treatment groups. UTI combined with MTH may serve a protective role by suppressing oxidative stress in the small intestinal mucosa following CPR in rats compared with either UTI or MTH treatment alone.

Intestinal pseudo-obstruction as the initial manifestation of systemic lupus erythematosus.

Small bowel obstruction is common in emergency departments. However, the exact cause of intestinal pseudo-obstruction (IPO) is often misdiagnosed. IPO is considered a severe manifestation of systemic lupus erythematosus (SLE). However, IPO is rare as the initial manifestation of SLE. This paper reports a female patient who presented with IPO as the initial manifestation and was ultimately diagnosed with SLE. The 31-year-old female was definitively diagnosed with SLE after IPO symptoms for 1 month. She then presented multiple organ dysfunction syndrome (MODS) leading to a poor prognosis. Patients with unexplained SBO symptoms should be aware of systemic diseases. Early diagnosis and prompt medical treatment are crucial to avoid unnecessary surgery and obtain satisfactory outcomes.

Single nucleotide polymorphisms in the CD40 gene associate with the disease susceptibility and severity in knee osteoarthritis in the Chinese Han population: a case-control study.

BACKGROUND: This study explored the association between single nucleotide polymorphisms (SNPs) in the CD40 gene, rs4810485 G > T and rs1883832 C > T, as well as disease susceptibility and severity in knee osteoarthritis (KOA) in the Chinese Han population. METHOD: Peripheral venous blood was collected from 133 KOA patients (KOA group) and 143 healthy people (control group) from December 2012 to November 2013. The patients in the KOA group were classified into mild, moderate and severe groups according to disease severity. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to test the genotypes of all subjects. Binary logistic regression analyses were performed to analyze the risk factors for KOA. RESULTS: The KOA group was significantly different from the control group in living environment (P < 0.05). The KOA group had a lower frequency of TT genotype and T allele distribution of rs4810485 G > T compared with the control group, and rs4810485 G > T TT genotype and T allele may associate with low incidence of KOA (all P < 0.05). Besides, T allele and mutant homozygous TT genotype of rs1883832 C > T increased the susceptibility to KOA. Genotype and allele distribution of rs4810485 G > T and rs1883832 C > T were significantly different among the mild, moderate and severe groups (P < 0.05). There were more patients with rs4810485 G > T GG genotype and rs1883832 C > T TT genotype in the severe group than other genotypes of these two SNPs. According to binary logistic regression analysis, rs4810485 G > T TT genotype could alleviate disease severity in KOA, rs1883832 C > T TT genotype increase the severity of KOA and living environment is an important external factor that affects KOA severity. CONCLUSIONS: These data provide evidences that rs4810485 G > T and rs1883832 C > T in the CD40 gene may be associated with disease susceptibility and severity in KOA.

Mitigation of reactive metabolite formation for a series of 3-amino-2-pyridone inhibitors of Bruton's tyrosine kinase (BTK).

Reactive metabolites have been putatively linked to many adverse drug reactions including idiosyncratic toxicities for a number of drugs with black box warnings or withdrawn from the market. Therefore, it is desirable to minimize the risk of reactive metabolite formation for lead molecules in optimization, in particular for non-life threatening chronic disease, to maximize benefit to risk ratio. This article describes our effort in addressing reactive metabolite issues for a series of 3-amino-2-pyridone inhibitors of BTK, e.g. compound 1 has a value of 459pmol/mg protein in the microsomal covalent binding assay. Parallel approaches were taken to successfully resolve the issues: establishment of a predictive screening assay with correlation association of covalent binding assay, identification of the origin of reactive metabolite formation using MS/MS analysis of HLM as well as isolation and characterization of GSH adducts. This ultimately led to the discovery of compound 7 (RN941) with significantly reduced covalent binding of 26pmol/mg protein.

Association between Wnt inhibitory factor-1 expression levels in articular cartilage and the disease severity of patients with osteoarthritis of the knee.

Wnt inhibitory factor (WIF)-1 is a potent extracellular Wnt antagonist which may be used as a potential molecular therapy for the treatment of inflammatory and autoimmune diseases. Although previous studies have demonstrated that WIF-1 has a protective role in experimental studies of arthritis, its role in the various disease grades of osteoarthritis (OA) remains unclear. A total of 40 patients with various stages of primary OA of the knee and 10 control subjects were enrolled in the present study. Articular cartilage specimens were harvested from subjects following total knee arthroplasty or knee above amputation. Disease severity was determined according to Modified Mankin score and cartilage tissues were ascribed to four groups: Normal, mild, moderate and severe lesions. WIF-1 expression levels in articular cartilage were measured using immunohistochemical techniques. WIF-1 expression levels were detected in all cartilage tissues. As compared with the controls, patients with OA exhibited significantly decreased WIF-1 expression levels in the articular cartilage (0.19±0.05 vs. 0.26±0.04; P<0.01). Furthermore, articular cartilage WIF-1 expression levels in the moderate and severe lesion groups were significantly reduced, as compared with the controls (P<0.01) and mild lesion group (P<0.05). Subsequent analysis demonstrated that articular cartilage WIF-1 expression levels were negatively correlated with the severity of disease (r=-0.896, P<0.001). In conclusion, the results of the present study suggested that WIF-1 expression levels in articular cartilage may be negatively associated with progressive joint damage in patients with OA of the knee; therefore, WIF-1 expression may be a potential indictor for monitoring OA disease severity.

Correlation between senescence-associated beta-galactosidase expression in articular cartilage and disease severity of patients with knee osteoarthritis.

AIM: The purposes of this study were to investigate senescence-associated beta-galactosidase (SA-beta-Gal) levels in articular cartilage of knee osteoarthritis (OA) and the relationship with severity of the disease. METHODS: All the 50 cartilage tissues, including normal (controls) and OA cartilage were ascribed to four groups of normal, mild lesions, moderate lesions and severe lesions on the basis of the modified Mankin score. Immunohistochemistry was used to assess the SA-beta-Gal expression in articular cartilage. RESULTS: No SA-beta-Gal staining was observed in the normal articular cartilage samples. SA-beta-Gal staining was found in a subset of the chondrocytes close to the lesion site of mild, moderate and severe damaged knee OA cartilage. The percentage of SA-beta-Gal-positive chondrocytes in articular cartilage was 0% in controls, 13.00 ± 5.77% in mild lesions, 31.65 ± 6.91% in moderate lesions and 51.95 ± 6.21% in severe lesions. SA-beta-Gal expression in mild lesions, moderate lesions and severe lesions was higher compared with that of controls (P < 0.0001). SA-beta-Gal expression in moderate lesions and severe lesions were higher with respect to mild lesion samples (P < 0.0001). SA-beta-Gal expression in severe lesions was elevated compared with those of moderate lesions (P < 0.0001). Subsequent analysis showed that articular cartilage SA-beta-Gal levels correlated with severity of disease (Spearman's ρ = 0.94, P < 0.0001). CONCLUSION: SA-beta-Gal expression in articular cartilage is associated with progressive knee OA joint damage and is a potential indictor of disease severity.