Iguratimod suppresses sclerostin and receptor activator of NF-κB ligand production via the extracellular signal-regulated kinase/early growth response protein 1/tumor necrosis factor alpha pathway in osteocytes and ameliorates disuse osteoporosis in mice

Disuse osteoporosis is a prevalent complication among patients afflicted with rheumatoid arthritis (RA). Although reports have shown that the antirheumatic drug iguratimod (IGU) ameliorates osteoporosis in RA patients, details regarding its effects on osteocytes remain unclear. The current study examined the effects of IGU on osteocytes using a mouse model of disuse-induced osteoporosis, the pathology of which crucially involves osteocytes. A reduction in distal femur bone mass was achieved after 3 weeks of hindlimb unloading in mice, which was subsequently reversed by intraperitoneal IGU treatment (30 mg/kg; five times per week). Histology revealed that hindlimb-unloaded (HLU) mice had significantly increased osteoclast number and sclerostin-positive osteocyte rates, which were suppressed by IGU treatment. Moreover, HLU mice exhibited a significant decrease in osteocalcin-positive cells, which was attenuated by IGU treatment. In vitro, IGU suppressed the gene expression of receptor activator of NF-κB ligand (RANKL) and sclerostin in MLO-Y4 and Saos-2 cells, which inhibited osteoclast differentiation of mouse bone marrow cells in cocultures. Although IGU did not affect the nuclear translocation or transcriptional activity of NF-κB, RNA sequencing revealed that IGU downregulated the expression of early growth response protein 1 (EGR1) in osteocytes. HLU mice showed significantly increased EGR1- and tumor necrosis factor alpha (TNFα)-positive osteocyte rates, which were decreased by IGU treatment. EGR1 overexpression enhanced the gene expression of TNFα, RANKL, and sclerostin in osteocytes, which was suppressed by IGU. Contrarily, small interfering RNA-mediated suppression of EGR1 downregulated RANKL and sclerostin gene expression. These findings indicate that IGU inhibits the expression of EGR1, which may downregulate TNFα and consequently RANKL and sclerostin in osteocytes. These mechanisms suggest that IGU could potentially be used as a treatment option for disuse osteoporosis by targeting osteocytes.

Osteoporosis and Osteopenia in patients with psoriatic arthritis: a single-center retrospective study

OBJECTIVE

It is known that fracture risk is increased in patients with psoriatic arthritis (PsA), however, there is no consensus on the association with osteoporosis. The purpose of this study was to elicit the rate of osteoporosis and the risk factors of osteoporosis in patients with PsA at our institution.

METHODS

The data in this study were extracted from 163 patients with PsA. Osteoporosis and osteopenia were defined based on the WHO definition. Osteoporosis was also diagnosed when a fragility vertebral compression fracture was observed.

RESULTS

The osteoporosis and osteopenia rates for PsA patients were 11.7% and 33.1%, respectively. The rates of osteoporosis and osteopenia in males were particularly high compared to previous reports, at 9.3% and 34.3%, respectively. Trabecular bone score (TBS) was considered age-appropriate for both males and females. Body mass index (BMI) and TBS were significantly lower in patients with osteoporosis.

CONCLUSIONS

In patients with PsA, males are at elevated risk of osteoporosis and associated fragility fractures even if they are under 50 years old. BMI was significantly lower in osteoporotic cases, suggesting the importance of bone mineral density testing and treatment in such cases.

Early full weight-bearing and gait exercise after cemented total ankle arthroplasty with modified antero-lateral approach

BACKGROUND

According to the conventional postoperative procedure after total ankle arthroplasty (TAA) against end-stage osteoarthritis (OA) and rheumatoid arthritis (RA), mobilization and weight-bearing is currently started after completion of wound healing. Recently, early mobilization for dorsiflexion after TAA with modified antero-lateral approach was reported to be feasible and safe. To investigate the further possibility of expediting rehabilitation, this study evaluated the feasibility and safety of early full weight-bearing and gait exercise after cemented TAA utilizing a modified antero-lateral approach.

MATERIALS AND METHODS

This retrospective, observational study investigated 23 consecutive ankles (OA: 14 ankles, RA: 9 ankles) that had received cemented TAA with a modified antero-lateral approach. These ankles were divided into three groups [1. conventional postoperative protocol: 8 ankles, 2. early dorsiflexion protocol: 7 ankles, 3. early dorsiflexion+full weight-bearing protocol: 8 ankles]. In group 3, after early dorsiflexion mobilization (day 3), full weight-bearing/gait exercise was started from 7 days after surgery (10 days after if malleolar osteotomy was added). Postoperative wound complications were observed and recorded. Number of days for hospitalization was also evaluated. Range of motion (ROM) of dorsiflexion/plantar flexion was measured. Patients also completed a self-administered foot evaluation questionnaire (SAFE-Q) and the scale of Japanese Society for Surgery of the Foot (JSSF) ankle/hindfoot score preoperatively and at final follow-up.

RESULTS

No postoperative complications related to wound healing were observed even after early full weight-bearing and gait exercise. Days for hospitalization was significantly shortened in early full weight-bearing and gait exercise group (group 3) from 35-38 days to 24 days. ROM for both dorsiflexion and plantar flexion significantly increased in group 3, furthermore all indices of SAFE-Q score also showed stronger significant improvement in group 3. JSSF score improved significantly after TAA in all groups.

CONCLUSION

Within this small number of cases, early full weight-bearing and gait exercise from 7 days after cemented TAA was feasible and safe with the modified antero-lateral approach. Combination of early dorsiflexion mobilization and weight-bearing/gait exercise contributed to shortening the hospitalization day, and improving ROM for both dorsiflexion and plantar flexion after surgery. Innovations in postoperative procedures for rehabilitation after TAA can be expected.

Paediatric pustulotic arthro-osteitis patient with an IL36RN variant, heterozygous c.115+6T>C, who was successfully treated with tonsillectomy: A case report and literature review

Pustulotic arthro-osteitis (PAO) is an infrequent condition, with its manifestation in children being even rare. Some reports propose an association between genetic variants and the onset of PAO. Currently, no definitive treatment protocol exists for paediatric patients with PAO. In this study, we present the paediatric case of PAO with an IL36RN variant who was successfully treated with tonsillectomy.

Long-term retention rates of anti-tumour necrosis factor and anti-interleukin-17 antibodies for patients with psoriatic arthritis

OBJECTIVE

While biologics have been used for the patients with psoriatic arthritis, there remains to be unknown concerning long-term retention rates. This study aims to present real-world data about long-term retention rates of biologics for the patients with psoriatic arthritis, and to undertake an analysis of the contributing factors.

METHODS

We examined retention rates and the reasons for discontinuation for biologics (adalimumab, certolizumab pegol, secukinumab, and ixekizumab) in 146 prescriptions (of which, 109 prescriptions were as naive) at our hospital since March 2010.

RESULTS

Throughout the entire course of the study, the 10-year retention rates were approximately 70% for adalimumab, 50% for ixekizumab, and 40% for secukinumab. When evaluating retention rates in the biologic-naïve subgroups, the 10-year retention rates were all approximately 70%. Regarding certolizumab pegol, the 3-year retention rate was approximately 75%. For adalimumab, a higher degree of arthritis at the initiation of treatment was found to correlate with an increased likelihood of secondary inefficacy. The main reason for discontinuation was secondary inefficacy, except for ixekizumab.

CONCLUSIONS

Each biologic exhibited a favourable long-term retention rate. The main reason for discontinuation was secondary inefficacy. Regarding adalimumab, secondary inefficacy was linked to the extent of arthritis upon treatment initiation.

Real-world retention rates of biologics in patients with rheumatoid arthritis

Although biologics have their own characteristics, there are no clear criteria for selecting them to treat the patients with rheumatoid arthritis. To assist in selecting biologics, we investigated the retention rates of biologics at our institution. We examined retention rates, and reasons for dropout for biologics in 393 cases and 605 prescriptions (of which 378 prescriptions were as naive) at our hospital since October 2003. Throughout the entire course of the study, etanercept (ETN) was the most frequently used biologic, followed by adalimumab (ADA) and tocilizumab (TCZ). When narrowed down to the later period from 2010, ETN was still the most used, followed by TCZ and abatacept (ABT). When the retention rates were compared in biologic naive patients, the retention rates were TCZ, ABT, ETN, certolizumab pegol (CZP), golimumab (GLM), infliximab (IFX), and ADA, in that order. The retention rates were better with the first use of each biologic. The main reasons for dropout were primary ineffectiveness, secondary ineffectiveness, and infection. ETN was the most used biologic in our hospital, with an increasing trend toward the use of non-TNF inhibitors. Retention rates were higher in non-TNF inhibitors.

Basic fibroblast growth factor promotes meniscus regeneration through the cultivation of synovial mesenchymal stem cells via the CXCL6-CXCR2 pathway

OBJECTIVE

To investigate the efficacy of basic fibroblast growth factor (bFGF) in promoting meniscus regeneration by cultivating synovial mesenchymal stem cells (SMSCs) and to validate the underlying mechanisms.

METHODS

Human SMSCs were collected from patients with osteoarthritis. Eight-week-old nude rats underwent hemi-meniscectomy, and SMSCs in pellet form, either with or without bFGF (1.0 × 106 cells per pellet), were implanted at the site of meniscus defects. Rats were divided into the control (no transplantation), FGF (-) (pellet without bFGF), and FGF (+) (pellet with bFGF) groups. Different examinations, including assessment of the regenerated meniscus area, histological scoring of the regenerated meniscus and cartilage, meniscus indentation test, and immunohistochemistry analysis, were performed at 4 and 8 weeks after surgery.

RESULTS

Transplanted SMSCs adhered to the regenerative meniscus. Compared with the control group, the FGF (+) group had larger regenerated meniscus areas, superior histological scores of the meniscus and cartilage, and better meniscus mechanical properties. RNA sequencing of SMSCs revealed that the gene expression of chemokines that bind to CXCR2 was upregulated by bFGF. Furthermore, conditioned medium derived from SMSCs cultivated with bFGF exhibited enhanced cell migration, proliferation, and chondrogenic differentiation, which were specifically inhibited by CXCR2 or CXCL6 inhibitors.

CONCLUSION

SMSCs cultured with bFGF promoted the expression of CXCL6. This mechanism may enhance cell migration, proliferation, and chondrogenic differentiation, thereby resulting in superior meniscus regeneration and cartilage preservation.

Anti-NF-κB peptide derived from nuclear acidic protein attenuates ovariectomy-induced osteoporosis in mice

NF-κB is a transcription factor that is activated with aging. It plays a key role in the development of osteoporosis by promoting osteoclast differentiation and inhibiting osteoblast differentiation. In this study, we developed a small anti-NF-κB peptide called 6A-8R from a nuclear acidic protein (also known as macromolecular translocation inhibitor II, Zn2+-binding protein, or parathymosin) that inhibits transcriptional activity of NF-κB without altering its nuclear translocation and binding to DNA. Intraperitoneal injection of 6A-8R attenuated ovariectomy-induced osteoporosis in mice by inhibiting osteoclast differentiation, promoting osteoblast differentiation, and inhibiting sclerostin production by osteocytes in vivo with no apparent side effects. Conversely, in vitro, 6A-8R inhibited osteoclast differentiation by inhibiting NF-κB transcriptional activity, promoted osteoblast differentiation by promoting Smad1 phosphorylation, and inhibited sclerostin expression in osteocytes by inhibiting myocyte enhancer factors 2C and 2D. These findings suggest that 6A-8R has the potential to be an antiosteoporotic therapeutic agent with uncoupling properties.

Preoperative degree of deformity and underlying disease affect the postoperative deformity of joint-preserving hallux valgus surgery

BACKGROUND

The combination of distal osteotomy with lateral dissection in joint-preserving surgery for severe hallux valgus deformity has recently begun to yield encouraging results. We examined the frequency of complications and risk factors of those for joint-preserving surgery in patients with and without rheumatoid arthritis (RA).

METHODS

A retrospective, observational study of 72 feet (27 patients with RA) was performed. The inclusion criteria were patients who underwent joint-preserving surgery for hallux valgus deformity at our hospital between January 2008 and March 2016 who could be followed up with for longer than 12 months.

RESULTS

The mean preoperative and immediate postoperative hallux valgus angles (HVA) were 41.8 and 4.4, respectively. The mean preoperative and immediate postoperative intermetatarsal angles between the first and second metatarsal bones (M1-M2A) were 14.6 and 5.8, respectively. At the final postoperative evaluation, the mean HVA was 8.8 and the mean M1-M2A was 6.4.Data were compared among the patients with complications (recurrent valgus deformity, varus deformity), and those without complications (normal HVA) at the final postoperative evaluation. The rate of RA in the varus deformity group was 71.4%, which tended to be higher than in other groups (p = .058). The mean preoperative HVA were 48.2 and 52.6 in the group of recurrent valgus deformity and varus deformity, which was higher than the normal HVA group (p = .001).

CONCLUSIONS

High preoperative HVA was a risk factor for the recurrence of valgus deformity. Most of the varus deformities were observed in the RA group with high preoperative HVA; therefore, caution should be exercised in operating on patients with severe deformity or those with RA.

LEVEL OF EVIDENCE

III.

Extensive subcutaneous emphysema of the thigh as a rare complication following total knee arthroplasty: A case report

INTRODUCTION AND IMPORTANCE OF THE CASE

This is the first report of subcutaneous emphysema of the thigh as a complication after total knee arthroplasty (TKA).

PRESENTATION OF CASE

A 78-year-old female patient with valgus knee arthropathy underwent TKA. Two days postoperatively, the patient experienced left thigh swelling and pain, and subcutaneous emphysema was detected upon palpation. Although the skin tone was comparable to the other side, the left thigh was tender and firm. The surgical wound did not exhibit erythema. Computed tomography imaging revealed emphysema in the subcutaneous and intermuscular regions of the left thigh. Gram stain and culture tests from arthrocentesis were negative, and blood culture results were also negative. As there was no fever or disturbance of consciousness, and the LRINEC score was 1, supportive care was provided to the patient. At 5 days postoperatively, there was an observable improvement in the emphysema, and by day 9 postoperatively, the emphysema had fully resolved.

CLINICAL DISCUSSION

There is a lack of documented cases reporting extensive subcutaneous emphysema of the thigh following TKA, suggesting it to be an exceedingly rare complication. In this case, we conducted a thorough investigation to assess the potential association of infection. Subsequently, the symptoms were successfully alleviated with supportive care without antibiotics.

CONCLUSION

The occurrence of subcutaneous emphysema in the thigh was identified as a postoperative complication following TKA. Blood tests, culture tests and LRINEC score can be valuable tools for differentiation.

Effect of Diluents on Active Pharmaceutical Ingredient Loss Until Patients Ingest Powder Formulation

In powder formulations, it is a problem that the required therapeutic dose is not obtained because of loss of the active pharmaceutical ingredient (API). In this study, we investigated three types of lactose diluents, which are widely used as pharmaceutical excipients, for dispensing prednisolone powder. Extra-fine crystalline lactose, commonly used as a diluent in compounding powder formulations, was used as a comparison. The effect of lactose on the API loss rate was examined by analyzing the amount of prednisolone in the powder formulation taken out of a single-dose package after dispensing. The results showed that Dilactose-F had the lowest API loss rate (22%), followed by powder lactose (37.8%), extra-fine crystalline lactose (45.9%), and crystal form lactose (48.6%), indicating that the use of Dilactose-F as a diluent significantly improved API loss when compounding the powder formulation. Because each mixture of commercial prednisolone powder and lactose was within acceptable uniformity and loss rate before packaging, we considered that API loss occurred when the powder was taken out of the single-dose package before patients ingested them. Then, the physical properties of these lactose types affecting the API loss rate were examined. Strong correlation was not found between flowability and the API loss rate, but particle size distribution and bulk density were strongly correlated with the API loss rate. Furthermore, Dilactose-F, which showed the lowest API loss rate, did not show an exothermic peak due to epimerization to anhydrous β -lactose in differential scanning calorimetry and showed a peak specific to β -lactose in powder X-ray diffractometer. These results suggested that in powder compounding where the API content is low, the physical properties of lactose, such as particle size distribution, bulk density, and crystalline form, are intricately related to API loss.

Early mobilization of dorsiflexion from 3 days after cemented total ankle arthroplasty with modified antero-lateral approach

BACKGROUND

According to the conventional postoperative procedure after total ankle arthroplasty (TAA), mobilization is currently started after completion of wound healing. To investigate the possibility of expediting rehabilitation, this study evaluated the feasibility and safety of early mobilization of dorsiflexion after cemented TAA utilizing a modified antero-lateral approach.

MATERIALS AND METHODS

This retrospective, observational study investigated 14 consecutive ankles that had received cemented TAA. Mobilization of dorsiflexion was started from 3 days after surgery. Postoperative wound complications including blister formation, eschar formation, wound dehiscence, peri-incisional decreased sensation were observed and recorded. Range of motion (ROM) of dorsiflexion/plantar flexion was measured. Patients also completed a self-administered foot evaluation questionnaire (SAFE-Q) and the scale of Japanese Society for Surgery of the Foot (JSSF) ankle/hindfoot score preoperatively and at final follow-up.

RESULTS

No postoperative complications related to wound healing were observed. ROM for dorsiflexion, SAFE-Q score, and JSSF score improved significantly after TAA.

CONCLUSION

Within this small number of cases, early mobilization of dorsiflexion from 3 days after cemented TAA was feasible and safe with the modified antero-lateral approach. Innovations in postoperative procedures for rehabilitation after TAA can be expected.

Association of the Clinical and Radiographic Findings at Onset With Future Joint Destruction in Patients With Rheumatoid Arthritis

OBJECTIVES

Since inflammation can cause joint destruction in patients with rheumatoid arthritis (RA), it is assumed that joints that are symptomatic at onset are at higher risk of joint destruction; however, this theory remains controversial. This study aimed to investigate whether the progression of joint destruction in hands and feet could be predicted from the clinical and radiographic findings at onset.

METHODS

This study included 75 patients who visited our hospital within one year after the onset of RA with at least 12 months of follow-up. We examined the positive predictive value (PPV) and the sensitivity of the clinical findings (swelling, tenderness, and squeeze test) and joint destruction at onset for the progression of joint destruction.

RESULTS

Sixty joints (45 metacarpophalangeal and proximal interphalangeal joints, 15 metatarsophalangeal joints) exhibited progressive structural destruction during the study course. Both the PPV and the sensitivity of the clinical findings for the progression of joint destruction were low; however, only the sensitivity of the squeeze test for the feet was high. The PPV of joint destruction at onset was higher than the clinical findings, and the sensitivity of joint destruction at onset was as high as the squeeze test for the feet.  Conclusions: Regular follow-up with imaging is necessary regardless of symptoms and joint destruction at the onset. Adding the squeeze test for feet to routine clinical practice may help predict the risk of joint destruction for the feet.

Effects of prior osteoporosis treatment on the treatment response of romosozumab followed by denosumab in patients with postmenopausal osteoporosis

In patients with postmenopausal osteoporosis, prior osteoporosis treatment affected the bone mineral density increase of following treatment with 12 months of romosozumab, although it did not affect that of following treatment with 12 months of denosumab after romosozumab.

PURPOSE

To investigate the effects of prior osteoporosis treatment on the response to treatment with romosozumab (ROMO) followed by denosumab (DMAb) in patients with postmenopausal osteoporosis.

METHODS

In this prospective, observational, multicenter study, treatment-naïve patients (Naïve; n = 55) or patients previously treated with bisphosphonates (BP; n = 37), DMAb (DMAb; n = 45) or teriparatide (TPTD; n = 17) (mean age, 74.6 years; T-scores of the lumbar spine [LS] - 3.2 and total hip [TH] - 2.6) were switched to ROMO for 12 months, followed by DMAb for 12 months. Bone mineral density (BMD) and serum bone turnover markers were evaluated for 24 months.

RESULTS

A BMD increase was observed at 12 and 24 months in the following patients: Naïve (18.2% and 22.0%), BP (10.2% and 12.1%), DMAb (6.6% and 9.7%), and TPTD (10.8% and 15.0%) (P < 0.001 between the groups at both 12 and 24 months) in LS and Naïve (5.5% and 8.3%), BP (2.9% and 4.1%), DMAb (0.6% and 2.2%), and TPTD (4.3% and 5.4%) (P < 0.01 between the groups at 12 months and P < 0.001 at 24 months) in TH, respectively. The BMD increase in LS from 12 to 24 months was negatively associated with the levels of bone resorption marker at 24 months. Incidences of major fragility fractures for the respective groups were as follows: Naïve (5.5%), BP (16.2%), DMAb (11.1%), and TPTD (5.9%).

CONCLUSIONS

Previous treatment affected the BMD increase of following treatment with ROMO, although it did not affect that of following treatment with DMAb after ROMO.

Modified Scarf Osteotomy with Medial Capsular Interposition Combined with Metatarsal Shortening Offset Osteotomy: A Comparison of Patients with Noninflammatory Arthritis and Rheumatoid Arthritis of the Foot

BACKGROUND

Patients who have noninflammatory arthritis of the feet may develop destructive changes on the first metatarsal head and painful dislocation of the metatarsophalangeal (MTP) joint of 1 or more lesser toes. This aim of this study was to compare feet with noninflammatory arthritis and those with rheumatoid arthritis (RA) with respect to the clinical and radiographic outcomes after treatment of these destructive deformities with a modified Scarf osteotomy with medial capsular interposition into the newly formed first MTP joint, combined with metatarsal shortening offset osteotomy.

METHODS

A retrospective observational study of 93 feet (31 with noninflammatory arthritis and 62 with RA) was performed. Hallux and lesser-toe scores on the Japanese Society for Surgery of the Foot (JSSF) scoring system, a self-administered foot evaluation questionnaire (SAFE-Q), and preoperative and postoperative radiographic parameters were evaluated.

RESULTS

There were significant improvements at the time of the final follow-up in the mean scores on the hallux and lesser-toe scales of the JSSF system and in the SAFE-Q score. The postoperative JSSF lesser-toes function score was better for the feet with noninflammatory arthritis feet than the feet with RA. There was no significant difference in the hallux valgus angle (HVA) between 1 month postoperatively and the final follow-up for both groups. Furthermore, the HVA showed a strong correlation between the 1-month and final follow-up values.

CONCLUSIONS

The combination of the modified Scarf osteotomy with medial capsular interposition and shortening metatarsal offset osteotomy was useful and safe in feet with noninflammatory arthritis. The HVA at 1 month after surgery is useful to predict the HVA within 5 years after surgery. The postoperative clinical score for the lesser toes was better in the feet with noninflammatory arthritis.

LEVEL OF EVIDENCE

Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Impact of wall shear stress affected by anatomical difference between acute and chronic coronary syndrome in patients with LAD proximal disease

 

Recent hemodynamic studies have demonstrated that progression of coronary atherosclerosis occurs at low wall share-stress site, whereas plaque rupture frequently occurs at high share stress site. It is well recognized that wall shear stress is relatively low along the outer walls of the bifurcation.

We investigated consecutive 140 patients (77 with acute coronary syndrome (ACS) and 63 with chronic coronary syndrome (CCS) performed PCI for LAD proximal lesions (AHA seg.6) from January 2016 to December 2019. In CCS group, entry criteria included stenosis of at least 90% in the LAD proximal lesion or at least 70% in the LAD proximal lesion and objective evidence of myocardial ischemia (inducible ischemia with either exercise or pharmacologic vasodilator stress or with pressure wire). Exclusion criteria were patients with maintenance dialysis, chronic total occlusion lesions, in-stent restenosis, and clinically diagnosed unstable angina without troponin I elevation. We measured the distance from LMT distal carina to the culprit site (Distance) and plaque location (Location) with intravascular ultrasound and angle between LMT and LAD with cardiovascular angiography analysis system (CAAS) (Angle).

The two groups were generally well balanced with regard to baseline clinical characteristics. The mean (±SD) age of the patients was 69.0±11.8 years, and 75% were men. Medication at baseline was also similar between two groups except higher prevalence of statin prescription in CCS group. The Distance was shorter and Angle was steeper in CCS group than in ACS group. The number of patients with Angle less than 150 degrees and with Location in the lateral wall side was much more in CCS group.

In this study, plaques in CCS were frequently observed at low shear stress site, whereas those in ACS at high shear stress site. Plaque progression in CCS may be associated with low wall shear stress, and high shear stress may play key role in plaque rupture in ACS. This anatomical difference can partly explain the different mechanisms of onset between of ACS and CCS.

Funding Acknowledgement

Type of funding sources: None. Anatomical differenceCharacteristics and results

Effects of iguratimod on glucocorticoid-induced disorder of bone metabolism in vitro

INTRODUCTION

Glucocorticoids are widely used to treat various diseases including rheumatoid arthritis (RA); however, one of the most frequent and severe adverse effects is glucocorticoid-induced osteoporosis (GIOP). Iguratimod (IGU) is a novel conventional synthetic disease-modifying anti-rheumatic drug developed in Japan. The aim of this study is to investigate the effects of IGU on glucocorticoid-induced disorder of bone metabolism in vitro.

MATERIALS AND METHODS

In osteoclastogenesis of mouse bone marrow-derived cells, tartrate-resistant acid phosphatase staining, resorption pit assay, western blotting, real-time polymerase chain reaction (PCR), and mRNA sequencing were performed. In osteoblastogenesis of MC3T3-E1 cells, alkaline phosphatase (ALP) staining and activity, alizarin red staining, and mRNA sequencing were performed, and real-time PCR and western blotting were conducted in MC3T3-E1 cells and murine osteocyte-like cell line MLO-Y4 cells.

RESULTS

IGU significantly suppressed a dexamethasone-induced increase in osteoclasts, differentiation, and bone resorption activity by inhibition of the receptor activator of the nuclear factor kappa-B (RANK)/tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6)/nuclear factor kappa-B (NFκB)-p52 pathway. In MC3T3-E1 cells, IGU significantly upregulated dexamethasone-induced downregulation of ALP activity, bone mineralization, and osteoblast-related gene and protein expression. In MLO-Y4 cells, IGU significantly upregulated dexamethasone-induced downregulation of the gene expression of ALP and osteocalcin, and also downregulated receptor activator of NFκB ligand (RANKL)/osteoprotegerin gene expression ratio without dexamethasone.

CONCLUSION

These results suggest that IGU may improve glucocorticoid-induced disorder of bone metabolism and may exhibit positive effects against GIOP associated with RA.

Effects of prior osteoporosis treatment on 12-month treatment response of romosozumab in patients with postmenopausal osteoporosis

OBJECTIVES

To investigate the effects of prior treatment and determine the predictors of a 12-month treatment response of romosozumab (ROMO) in 148 patients with postmenopausal osteoporosis.

METHODS

In this prospective, observational, and multicenter study, treatment naïve patients (Naïve; n=50) or patients previously treated with bisphosphonates (BP; n=37) or denosumab (DMAb; n=45) or teriparatide (TPTD; n=16) (mean age, 75.0 years; T-scores of the lumbar spine [LS] -3.2 and total hip [TH] -2.6) were switched to ROMO due to insufficient effects of prior treatment. Bone mineral density (BMD) and serum bone turnover markers were evaluated for 12 months.

RESULTS

At 12 months, changes in LS BMD were Naïve (18.2%), BP (10.2%), DMAb (6.4%), and TPTD (11.2%) (P<0.001 between groups) and changes in TH BMD were Naïve (5.6%), BP (3.3%), DMAb (0.6%), and TPTD (4.4%) (P<0.01 between groups), respectively. In all groups, the LS BMD significantly increased from baseline at 6 and 12 months, although only the DMAb group failed to obtain a significant increase in TH BMD during 12-month treatment. Mean values of N-terminal type I procollagen propeptide (PINP; μg/L) from baseline → 1 month → 12 months were Naïve (67.9 → 134.1 → 51.0), BP (32. 2 → 81.7 → 40.9), DMAb (30.4 → 56.2 → 75.3), and TPTD (97.4 → 105.1 → 37.1), and those of isoform 5b of tartrate-resistant acid phosphatase (TRACP-5b; mU/dL) were Naïve (500.4 → 283.8 → 267.1), BP (273.4 → 203.1 → 242.0), DMAb (220.3 → 246.1 → 304.8), and TPTD (446.6 → 305.1 → 235.7), respectively. Multiple regression analysis revealed that the significant predictors of BMD change at 12 months were difference of prior treatment (r=-2.8, P<0.001) and value of PINP at 1 month (r=0.04, P<0.01) for LS, and difference of prior treatment (r=-1.3, P<0.05) and percentage change of TRACP-5b at 1 month (r=-0.06, P<0.05) for TH.

CONCLUSIONS

The early effects of ROMO on LS and TH BMD increase at 12 months were significantly affected by the difference of prior treatment and are predicted by the early change in bone turnover markers.

Effects of prior osteoporosis treatment on early treatment response of romosozumab in patients with postmenopausal osteoporosis

PURPOSE

To investigate the effects of prior treatment and the predictors of early treatment response to romosozumab (ROMO) in patients with postmenopausal osteoporosis.

METHODS

In this prospective, observational, multicenter study, 130 treatment-naïve patients (Naïve; n = 37) or patients previously treated with bisphosphonates (BP; n = 33), denosumab (DMAb; n = 45), or teriparatide (TPTD; n = 15) (age, 75.0 years; T-scores of the lumbar spine [LS] -3.2 and femoral neck [FN] -2.9) were switched to ROMO based on their physician's decision. Bone mineral density (BMD) and serum bone turnover markers were evaluated for six months.

RESULTS

At six months, LS BMD changes were 13.6%, 7.5%, 3.6%, and 8.7% (P < .001 between groups) and FN BMD changes were 4.2%, 0.4%, 1.6%, and 1.5% (P = .16 between groups) for Naïve, BP, DMAb, and TPTD groups, respectively. Changes in N-terminal type I procollagen propeptide (PINP; μg/L) levels from baseline → one month were 72.7 → 139.0, 33.5 → 85.4, 30.4 → 54.3, and 98.4 → 107.4, and those of isoform 5b of tartrate-resistant acid phosphatase (TRACP-5b) (mU/dL) were 474.7 → 270.2, 277.3 → 203.7, 220.3 → 242.0, and 454.1 → 313.0 for Naïve, BP, DMAb, and TPTD groups, respectively. Multivariate regression analysis revealed that significant predictors of LS BMD change at six months were prior treatment difference (r = -3.1, P = .0027) and TRACP-5b percentage change (r = -2.8, P = .0071) and PINP value at one month (r = 3.2, P = .0021).

CONCLUSION

Early effects of ROMO on the increase in LS BMD are significantly affected by the difference of prior treatment and are predicted by the early change in bone turnover markers.

MINI ABSTRACT

Early effects of ROMO on the increase in LS BMD at six months is significantly affected by the difference of prior treatment and also predicted by the early change of bone turnover markers in patients with postmenopausal osteoporosis.

A report of three cases which required tibialis anterior tendon resection to recover delayed wound healing after total ankle arthroplasty in patients with rheumatoid arthritis

Delayed wound healing is one of the severe complications after total ankle arthroplasty (TAA). In particular, once tibialis anterior (TA) tendon is exposed from tendon sheath of extensor retinaculum, wound healing will be critically intractable. We report three cases (mean age: 75.3 years old) of delayed wound healing after TAA cured by resection of TA tendon in patients with rheumatoid arthritis (RA). All three cases underwent TAA through an anterior approach, with careful suture of extensor retinaculum in wound closure. Ankle joint was fixed with splint and avoid weight bearing for three weeks after surgery. Delayed wound healing with TA tendon exposure was observed, and initially treated by debridement, basic fibroblast growth factor spray, and negative pressure wound therapy, which all failed to obtain wound healing. Finally, complete resection of TA tendon led to rapid wound healing. In all cases, ankle dorsal flexion was compensated by other extensors, with maintained range of motion and muscle strength (manual muscle testing 3 to 4) compared to pre-operation at 1 year after TAA operation. Resection of TA tendon may be considered as one of the salvage treatment options of severe delayed wound healing in TAA with anterior approach, especially in elderly patients.

Combined effect of teriparatide and an anti-RANKL monoclonal antibody on bone defect regeneration in mice with glucocorticoid-induced osteoporosis

OBJECTIVE

The purpose of this study was to examine the effect of single or combination therapy of teriparatide (TPTD) and a monoclonal antibody against the murine receptor activator of nuclear factor κB ligand (anti-RANKL Ab) on cancellous and cortical bone regeneration in a mouse model of glucocorticoid-induced osteoporosis (GIOP).

METHODS

C57BL/6 J mice (24 weeks of age) were divided into five groups: (1) the SHAM group: sham operation + saline; (2) the prednisolone (PSL) group: PSL + saline; (3) the TPTD group: PSL + TPTD; (4) the Ab group: PSL + anti-RANKL Ab; and (5) the COMB group: PSL + TPTD + anti-RANKL Ab (n = 8 per group). With the exception of the SHAM group, 7.5 mg of PSL was inserted subcutaneously into mice, to generate a mouse model of GIOP. Four weeks after insertion, bone defects with a diameter of 0.9 mm were created to assess bone regeneration on both femoral metaphysis (cancellous bone) and diaphysis (cortical bone). After surgery, therapeutic intervention was continued for 4 weeks. Saline (200 μl) or TPTD (40 μg/kg) was injected subcutaneously five times per week, whereas the anti-RANKL Ab (5 mg/kg) was injected subcutaneously once on the day after surgery. Subsequently, the following analyses were performed: microstructural assessment of bone regeneration and bone mineral density (BMD) measurement via micro-computed tomography, and histological, histomorphometrical, and biomechanical analyses with nanoindentation.

RESULTS

The COMB group showed the highest lumbar spine BMD increase (vs. the PSL, TPTD, and Ab groups). The volume of regenerated cancellous bone at the bone defect site was higher in the COMB group compared with the PSL, TPTD, and Ab group. The volume of the regenerated cortical bone was significantly higher in the COMB group compared with the PSL group, and its hardness was significantly higher in the COMB group compared with the PSL and TPTD groups.

CONCLUSION

In a mouse model of glucocorticoid-induced osteoporosis, the combination therapy of TPTD plus the anti-RANKL Ab increased bone mineral density in the lumbar spine and regenerated cancellous bone volume compared with single administration of each agent, and also increased regenerated cortical bone strength compared with single administration of TPTD.

Effects of follow-on therapy after denosumab discontinuation in patients with postmenopausal osteoporosis

OBJECTIVES

To clarify the effects of follow-on therapy after denosumab (DMAb) discontinuation.

METHODS

In this retrospective, multicenter study, postmenopausal patients with osteoporosis who were previously treated by oral bisphosphonates (BP) (n = 26) or teriparatide (TPTD) (n = 27) were switched to DMAb (administered 2.6 times), and then discontinued. Patients (73.1 years, T-scores of the lumbar spine [LS] - 2.7 and femoral neck [FN] - 2.2) were switched to either (1) raloxifene (RAL) (n = 13) or BP [(2) weekly or monthly BP (wmBP) (n = 29) or (3) zoledronate (ZOL) (n = 11)], based on each physician's decision (mean interval after final DMAb administration was 7.2 months). Bone mineral density (BMD) at final DMAb administration were set as baseline.

RESULTS

Changes in LS BMD at 1.5 years after final DMAb administration were -2.7% in the RAL, 0.7% in the wmBP, and 1.9% in the ZOL (p = .31 between groups), and in FN BMD were -3.8%, -0.8%, and 1.8%, respectively (p = .02 between the RAL and ZOL; p = .048 between the RAL and BP). Clinical vertebral fracture incidence during 1.5 years after final DMAb administration was 23.1% in the RAL, 3.4% in the wmBP, and 0.0% in the ZOL (p = .048 between the RAL and ZOL; p = .015 between the RAL and BP). No significant differences were observed in these parameters between the wmBP and ZOL.

CONCLUSION

These results may contribute to the selection of adequate follow-on therapy after DMAb discontinuation, although further investigations are required.

A55 LACK OF EXPERIMENTAL REPRODUCIBILITY IN PRECLINICAL RESEARCH IS INFLUENCED BY THE NUTRITIONAL PROFILE OF STANDARD RODENT CHOWS

Background

Lack of experimental reproducibility, particularly in studies investigating the microbiota, is of growing concern to the scientific community. Factors such as environment, stress, and sex have been identified as contributors, whereas dietary composition has received less attention.

Aims

To profile the use of standard rodent chows in research institutions, analyze the nutrient content of common rodent chows, and assess the impact of different chows on microbiota profiles.

Methods

A survey was conducted to evaluate which rodent chows are used by research institutions worldwide. Seven standard rodent chows were selected for analysis of ingredients, fermentable carbohydrate (FODMAP) and gluten content. FODMAP content was measured by high-performance liquid-chromatography and enzymatic assays, and gluten content was assessed by a commercial kit using G12 antibody. Forty C57BL/6 mice were randomized to 4 groups of 10 mice (5 male, 5 female). Group A was euthanized at baseline. Group B received the breeding institution chow (LabDiet 5066). Group C received ResearchDiets AIN93G (low FODMAP and gluten content). Group D received LabDiet 5001 (high FODMAP and gluten content). After 3 weeks, cecal contents were collected and analyzed by 16S rRNA gene sequencing; short- and branched-chain fatty acids (SCFA, BCFAs) content was also determined.

Results

Twenty-eight different types of rodent chows were reported to be used by 45 international survey respondents. Ingredient composition of the standard chows varied widely, resulting in differences in FODMAP and gluten content. Microbiota analysis of cecal contents revealed that gut microbiota composition was altered by the standard chows, as reflected by significantly different clusters in β-diversity analysis as well as by altered α-diversity. Microbiota diversity was also influenced by sex in Groups A and B (p&lt;0.01). Total SCFA levels were lower (p=0.03) and BCFA levels were higher (p=0.01) in Group C compared to Group B.

Conclusions

Our results suggest that the composition of the diet not only significantly impacts gut microbiota profiles and fermentation patterns but may also emphasize sex differences in preclinical studies, with major implications for the reproducibility of results across laboratories.

Funding Agencies

CIHRThe Canadian Nutrition Society

Impact of combining medial capsule interposition with modified scarf osteotomy for hallux valgus

Objectives: To clarify the effect of combining medial capsule interposition with modified scarf osteotomy for hallux valgus.Methods: A multicenter, retrospective study included 64 cases [59 osteoarthritis patients (excluding rheumatoid arthritis); age 68.8 years, range 40-93 years] of modified scarf osteotomy which were performed from 2013 to 2017 and followed for 26.6 (range, 13-50) months. Patients were treated by either (1) without medial capsule interposition (33 cases) or (2) combined with interposition (31 cases) at each senior surgeon's discretion. The Japanese Society for Surgery of the Foot (JSSF) hallux metatarsophalangeal (MTP)-interphalangeal scale was evaluated along with radiographic parameters (hallux valgus angle [HVA], first and second metatarsals intermetatarsal angles, and Hardy grade).Results: All JSSF scale and radiographic parameters were similar at baseline and significantly improved at final follow-up in both groups (pre-operation vs. final follow-up: p < .001). However, compared to without interposition group, interposition group showed significantly higher improvement in the JSSF scale (pre-operation to final follow-up: p value between the two groups at final follow-up) for pain (without interposition: 19.4-34.2, interposition: 18.4-37.1; p = .02), function (without interposition: 20.8-33.6, interposition: 18.3-36.6; p = .005), total score (without interposition: 41.5-81.8, interposition: 38.5-88.5; p < .001), and the MTP joint space (without interposition: 1.4-1.5 mm, interposition: 1.6-2.6 mm; p < .001) with significant correlation between the total JSSF score (r = .40; p = .001).Conclusion: Combining medial capsule interposition with modified scarf osteotomy significantly improved mid-term clinical outcomes.

Bone stock reconstruction for huge bone loss using allograft-bones, bone marrow, and teriparatide in an infected total knee arthroplasty

Bone stock reconstruction using allograft-bones, bone marrow (BM), and teriparatide (TPTD) is reported. Huge and extensive bone losses occurred in the medullary cavity of the femur and tibia of a 55-year-old female rheumatoid arthritis patient with severe osteoporosis after debridement of her infected total knee arthroplasty. Because of the risks of unstable prosthetic fixation and intra-operation fracture, we first reconstructed the bone stock. Chipped allograft bones mixed with BM were implanted in the bone defects, and TPTD was administrated for the osteoporosis therapy. Good bone formation was found by computed tomography after 4 months. Bone turnover markers and bone mineral density (BMD) were increased at 6 months. We confirmed good bone formation at the re-implantation surgery. The newly formed bone harvested during the re-implantation surgery showed active osteoblast-like lining cells. TPTD is known to enhance allograft bone union, mesenchymal stem cell differentiation into osteoblasts, and BMD. This tissue engineering-based technique might be improved by the various effects of TPTD. This method without any laboratory cell culture might be a good option for bone stock reconstruction surgery in ordinary hospitals.

Albumin and apolipoprotein H mRNAs in human plasma as potential clinical biomarkers of liver injury: analyses of plasma liver-specific mRNAs in patients with liver injury

CONTEXT

Plasma liver-specific mRNAs are useful biomarkers of hepatotoxicity in rats.

OBJECTIVE

To investigate the potential application of liver-specific mRNAs as biomarkers for liver injury in humans.

METHODS

We determined the plasma levels of liver-specific mRNAs by real-time qRT-PCR in healthy donors and patients with liver injury.

RESULTS

Plasma levels of albumin (ALB) and apolipoprotein H (APOH) mRNAs increased in patients with elevated serum alanine aminotransferase. These mRNAs also increased in plasma after transcatheter arterial chemoembolization, which induces specific injury to liver.

CONCLUSIONS

We demonstrated the potential application of plasma ALB and APOH mRNAs as clinical biomarkers for liver injury.

Factors that predict in-hospital mortality in eosinophilic granulomatosis with polyangiitis

BACKGROUND

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare systemic small-vessel vasculitis associated with asthma, eosinophilia, and necrotizing vasculitis. EGPA is potentially life-threatening and often involves peripheral neuropathies, peptic ulcers, cerebral vessel disease, and cardiovascular disease. However, there is limited understanding of the prognostics factors for patients with EGPA. We investigated the clinical features and factors affecting patients' in-hospital mortality, using a national inpatient database in Japan.

METHODS

We retrospectively collected data of EGPA patients who required hospitalization between July 2010 and March 2013, using the Diagnosis Procedure Combination database. We evaluated EGPA patients' characteristics and performed multivariate logistic regression analyses to assess the factors associated with in-hospital mortality.

RESULTS

A total of 2195 EGPA patients were identified. The mean age was 61.9 years, 42.1% (924/2195) were male, and 41.6% (914/2195) had emergent admission. In-hospital deaths occurred in 97/2195 patients (4.4%). Higher in-hospital mortality was associated with age older than 65 years, disturbance of consciousness on admission, unscheduled admission, respiratory disease, cardio-cerebrovascular disease, renal disease, sepsis, and malignant disease on admission. Lower mortality was associated with female gender and peripheral neuropathies.

CONCLUSIONS

Our study revealed the clinical features of EGPA patients who required hospitalization and the factors associated with their mortality. These results may be useful for physicians when assessing disease severity or treatments for hospitalized EGPA patients.

Identification of novel liver-specific mRNAs in plasma for biomarkers of drug-induced liver injury and quantitative evaluation in rats treated with various hepatotoxic compounds

Circulating liver-specific mRNAs such as albumin (Alb) and α-1-microglobulin/bikunin precursor (Ambp) have been reported to be potential biomarkers for drug-induced liver injury (DILI). We identified novel circulating liver-specific mRNAs and quantified them, together with the two previously reported mRNAs, in plasma from rats treated with various hepatotoxicants to validate circulating liver-specific mRNAs as biomarkers for DILI. Among six genes selected from the database, high liver specificity of apolipoprotein h (Apoh) and group-specific component (Gc) mRNAs were confirmed by reverse transcription (RT)-PCR and the copy numbers of these mRNAs elevated in plasma from rats treated with thioacetamide. Liver-specific mRNAs (Alb, Ambp, Apoh, and Gc) were quantified by real-time RT-PCR in plasma from rats with single dosing of seven hepatotoxicants. There were noticeable interindividual and intercompound variabilities in the severity of liver injury. The levels of four mRNAs increased almost in parallel and correlated with changes in the alanine aminotransferase (ALT) values and the hepatocellular necrosis scores at 24h after dosing. It was noteworthy that the magnitude of the increases in mRNA levels was greater than that in the ALT value. Time course analysis within 24h after dosing revealed that the timing of the increase was different among mRNA species, and the plasma levels of Alb and Gc mRNAs increased substantially earlier than the ALT values, suggesting that patterns of changes in circulating liver-specific mRNAs indicate the progression of liver injury. These results strongly support the reliability and usefulness of the four circulating liver-specific mRNAs as biomarkers for DILI.

Determination of appropriate stage of human-induced pluripotent stem cell-derived cardiomyocytes for drug screening and pharmacological evaluation in vitro

Human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs) at different stages (approximate days 30, 60, and 90) were used to determine the appropriate stage for functional and morphological assessment of drug effects in vitro. The hiPS-CMs had spontaneous beating activity, and β-adrenergic function was comparable in all stages of differentiation. Microelectrode array analyses using ion channel blockers indicated that the electrophysiological properties of these ion channels were comparable at all differentiation stages. Ultrastructural analysis using electron microscopy showed that myofibrillar structures at days 60 and 90 were similarly distributed and more mature than that at day 30. Analysis of motion vectors in contracting cells showed that the velocity of contraction was the highest at day 90 and was the most mature among the three stages. Gene expression analysis demonstrated that expression of some genes related to myofilament and sarcoplasmic reticulum increased with maturation of morphological and contractile properties. In conclusion, day 30 cardiomyocytes are useful for basic screening such as the assessment of electrophysiological properties, and days 60 and 90 are the appropriate differentiation stage for morphological assays. For the assay of contractile function associated with subcellular components such as sarcoplasmic reticulum, day 90 cardiomyocytes are the most suitable.

A novel purification method of murine embryonic stem cell- and human-induced pluripotent stem cell-derived cardiomyocytes by simple manual dissociation

Cardiomyocytes derived from embryonic stem cells (ES-CMs) and induced pluripotent stem cells (iPS-CMs) are useful for toxicity and pharmacology screening. In the present study, we found that cardiomyocyte-rich beating cell clusters (CCs) emerged from murine embryonic stem cell (mESC)-derived beating EBs and from human-induced pluripotent stem cell (hiPSC)-derived beating EBs dissociated by gentle pipetting with a thin glass pipette. The percentage of cardiac troponin T (cTnT)-positive cells in the beating CCs obtained from mESC-derived and hiPSC-derived beating EBs was higher (81.5% and 91.6%, respectively) than in beating-undissociated EBs (13.7% and 67.1%, respectively). For mESCs, the yield of cTnT-positive cells from beating CCs was estimated to be 1.6 times higher than that of beating EBs. The bromodeoxyuridine labeling index of mouse ES-CMs and human iPS-CMs in beating CCs was 1.5- and 3.2-fold, respectively, greater than those in beating EBs. To investigate the utility of the cells in toxicity assessment, we showed that doxorubicin, a cardiotoxic drug, induced myofilament disruption in cardiomyocytes isolated by this method. This simple method enables preparation of mouse ES-CMs and human iPS-CMs with better proliferative activity than beating EBs not dissociated by pipetting, and the cardiomyocytes are useful for drug-induced myocardial toxicity testing.

Electrical conduction of organic ultrathin films evaluated by an independently driven double-tip scanning tunneling microscope

The electrical transport properties of organic thin films within the micrometer scale have been evaluated by a laboratory-built independently driven double-tip scanning tunneling microscope, operating under ambient conditions. The two tips were used as point contact electrodes, and current in the range from 0.1 pA to 100 nA flowing between the two tips through the material can be detected. We demonstrated two-dimensional contour mapping of the electrical resistance on a poly(3-octylthiophene) thin films as shown below. The obtained contour map clearly provided an image of two-dimensional electrical conductance between two point electrodes on the poly(3-octylthiophene) thin film. The conductivity of the thin film was estimated to be (1-8) × 10(-6) S cm(-1). Future prospects and the desired development of multiprobe STMs are also discussed.

Gene expression profiling of functional murine embryonic stem cell-derived cardiomyocytes and comparison with adult heart: profiling of murine ESC-derived cardiomyocytes

Although embryonic stem cell (ESC)-derived cardiomyocytes may be a powerful tool in drug discovery, their potential has not yet been fully explored. Nor has a detailed comparison with adult heart tissue been performed. We have developed a method for efficient production of cardiomyocyte-rich embryoid bodies (EBs) from murine ESCs. Analysis of global gene expression profiles showed that EBs on day 7 and/or 21 of differentiation (d7CMs and d21CMs, respectively) were similar to adult heart tissue for genes categorized as regulators of muscle contraction or voltage-gated ion channel activity, although d21CMs were more mature than d7CMs for contractile components related to morphological structures. Calcium and sodium channel blockers altered Ca2+ transients, and isoproterenol, a beta-adrenergic compound, increased the rate of beating in d7CMs and d21CMs. Our gene analytic system therefore enabled us to identify genes that are expressed in the physiological pathways associated with ion channels and structural components in d7CMs and d21CMs. We conclude that EBs might be of use for the basic screening of drugs that might affect contractile function through ion channels.

Detection of cell-free, liver-specific mRNAs in peripheral blood from rats with hepatotoxicity: a potential toxicological biomarker for safety evaluation

To verify the concept that cell-free organ/tissue-specific mRNAs leaking from drug-damaged organs/tissues into peripheral blood could be toxicological biomarkers for identification of the target organs of drug toxicity, we attempted to detect liver-specific mRNAs in peripheral blood from rats with chemical-induced hepatotoxicity. We selected alpha(1)-microglobulin/bikunin precursor (Ambp) and albumin mRNAs as tentative liver-specific biomarkers and successfully detected them by reverse transcription (RT)-PCR in peripheral blood 24 h after D-galactosamine HCl (D-gal) or acetaminophen administration. Moreover, albumin mRNA was detected 2 h after D-gal administration, although plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were still unchanged. On the other hand, in peripheral blood from rat with bupivacaine HCl-induced skeletal muscle damage, neither Ambp nor albumin mRNA was detectable while plasma creatine kinase, ALT, and AST levels prominently increased 2 or 12 h after dosing. Furthermore, Ambp mRNA was also detectable in filtered plasma from rats with liver damage, indicating that cell-free Ambp mRNA can be present in peripheral blood. In conclusion, cell-free, liver-specific Ambp, and albumin mRNAs were detectable in peripheral blood from rats with chemical-induced liver damage. It is believed that the detection of cell-free organ/tissue-specific mRNA in peripheral blood is a promising approach in the survey of toxicological biomarkers.

[Extrapleural pneumonectomy for relapsed solitary fibrous tumors of the pleura with pleural dissemination]

We report a case of a 62-year-old female with a prior thoracotomy for solitary fibrous tumor of the diaphragmatic pleura. There was no clear evidence of malignant solitary fibrous tumor of the pleura (SFTP). In the 19th postoperative month, she had a disseminated recurrence of SFTP in the left thoracic cavity. There was no evidence of metastasis from medical imaging. Accordingly, a left extrapleural pneumonectomy was performed. Pathological examination revealed a disseminated recurrence of malignant SFTP, showing a higher grade of malignancy, because the resected specimen was identical to the only section suspicious of malignancy in the previous tumor. She had no complaint and kept better performance status until the 7th postoperative month after the re-resection, when she had a recurrence in the left thoracic cavity and dissemination in the peritoneal cavity. She died of the recurrence 15 months after the re-resection and 34 months after the prior thoracotomy.

Survey of Cryptosporidium spp. and Giardia spp. infections in various animals at a zoo in Japan

A total of 284 fecal samples of 89 species (43 mammalian species and 46 avian species) were examined for Cryptosporidium oocysts and Giardia cysts from 1999 to 2002. Each sample was collected at the zoo located at Osaka in Japan and examined by microscopy after performing the sucrose flotation method and by two immunofluorescent assay kits for detection of Cryptosporidium oocysts and Giardia cysts. Cryptosporidium spp. was found only in a raccoon dog (Nyctereutes procyonoides), and Giardia spp. was detected in a mandarin duck (Aix galericulata) and two ruddy shelducks (Tadorna ferruginea). In this study, the prevalences of these parasites were found to be low. However, these results suggested that the infected animals could serve as a source of contamination for surface water. This is the first report about the survey of Cryptosporidium spp. and Giardia spp. at a zoo in Japan.

Improved toxicogenomic screening for drug-induced phospholipidosis using a multiplexed quantitative gene expression ArrayPlate assay

We previously showed that a toxicogenomics analysis of drug-induced phospholipidosis enabled the identification of 12 specific gene markers and the establishment of an in vitro real-time PCR screening assay for the assessment of the phospholipidosis-inducing potential of compounds. The purpose of this study was to transfer our PCR-based assay into a 96-well microplate-based multiple mRNAs measuring assay (ArrayPlate assay) in order to increase throughput. Specifically, we determined the expression of the 12 marker genes using real-time PCR and ArrayPlate in human hepatoma HepG2 cells that were treated for 24h with each of amiodarone and 80 proprietary compounds. The following three performance criteria were satisfied in the ArrayPlate analysis: 1. Sensitivity-the expression of mRNA for all target genes was detected at quantifiable levels. 2. Repeatability-signal intensities and fold change values of each marker gene were highly repeatable. 3. Correlation-fold change values and their average values, which were used as indices of phospholipidosis induction potential, showed apparent correlation between the ArrayPlate and real-time PCR assays. Thus, the in vitro screening assay for compound-induced phospholipidosis should be transferable from a PCR-based assay to the higher-throughput ArrayPlate-based method.

Suppression of tumorigenicity, but not anchorage independence, of human cancer cells by new candidate tumor suppressor gene CapG

Previously, we isolated a series of cell lines from a human diploid fibroblast lineage as a model for multistep tumorigenesis in humans. After passaging a single LT-transfected fibroblast clone, differently progressed cell lines were obtained, including immortalized, anchorage-independent and tumorigenic cell lines. In the present paper, we analysed the gene expression profiles of these model cell lines, and observed that expression of the CapG protein was lost in the tumorigenic cell line. To examine the possibility that loss of CapG protein expression was required for tumorigenic progression, we transfected CapG cDNA into the tumorigenic cell line and tested for tumor-forming ability in nude mice. Results showed that ectopic expression of CapG suppressed tumorigenicity, but not growth in soft agar or liquid medium. We also found that certain cancer cell lines including stomach cancer, lung cancer and melanoma had also lost CapG expression. One such cancer cell line AZ521 also became non-tumorigenic after the introduction of CapG cDNA. Moreover, we showed that CapG expression was repressed in small-cell lung cancer tissues. Together, our findings indicated that CapG is a new tumor suppressor gene involved in the tumorigenic progression of certain cancers.

A toxicogenomic approach to drug-induced phospholipidosis: analysis of its induction mechanism and establishment of a novel in vitro screening system

Phospholipidosis is a lipid storage disorder in which excess phospholipids accumulate within cells. Some cationic amphiphilic compounds are known to have the potential to induce phospholipidosis. This study was undertaken to examine the molecular mechanisms that contribute to the development of phospholipidosis and to identify specific markers that might form the basis of an in vitro screening test. Specifically, we performed a large-scale gene expression analysis using DNA microarrays on human hepatoma HepG2 cells after they were treated with each of 12 compounds known to induce phospholipidosis. In electron microscopy, HepG2 cells developed lamellar myelin-like bodies in their lysosomes, the characteristic change of phospholipidosis, after treatment with these compounds for 72 h. DNA microarray analysis performed 6 and 24 h after treatment showed alterations in gene expression reflecting the inhibition of lysosomal phospholipase activity and lysosomal enzyme transport, and the induction of phospholipid and cholesterol biosynthesis. Seventeen genes that showed a similar expression profile following treatment were selected as candidate markers. Real-time PCR analysis confirmed that 12 gene markers showed significant concordance with lamellar myelin-like body formation. Furthermore, the average fold change values of these markers correlated well with the magnitude of this pathological change. In conclusion, microarray analysis revealed that factors such as alterations in lysosomal function and cholesterol metabolism were involved in the induction of phospholipidosis. Furthermore, comprehensive gene expression analysis enabled us to identify biomarkers of this condition that we then used to develop a rapid and sensitive in vitro screening test for drug-induced phospholipidosis.

Production of intergeneric somatic hybrids between round kumquat (Fortunella japonica Swingle) and 'Morita navel' orange (Citrus sinensis Osbeck)

Intergeneric somatic hybrids between embryogenic callus-derived protoplasts of round kumquat (Fortunella japonica Swingle) and 'Morita navel' orange (Citrus sinensis Osbeck) were produced by electrofusion. Among the eight different fusion strains obtained, six showed normal morphology, whereas the remaining two showed malformation. All the regenerated plants were intermediate in leaf morphology and had thick and round leaves, which are typical characteristics of polyploids. Ploidy analyses by flow cytometry and chromosome counting in root-tip cells revealed that these plants are amphidiploid (2n=4x=36). Hybridity of the fusion products was confirmed by random amplified polymorphic DNA and cleaved amplified polymorphic sequence (CAPS) analyses. Furthermore, analyses of chloroplast (cp) and mitochondrial (mt) DNA by CAPS showed that these somatic hybrids contained cp- and mt-DNA of round kumquat without recombination in the regions analyzed.