In vivo properties of KNT-127, a novel δ opioid receptor agonist: receptor internalization, antihyperalgesia and antidepressant effects in mice

BACKGROUND AND PURPOSE

Activation of δ opioid (DOP) receptors regulates pain and emotional responses, and also displays ligand-biased agonism. KNT-127 (1,2,3,4,4a,5,12,12a-octahydro-2-methyl-4aβ,1β-([1,2]benzenomethano)-2,6-diazanaphthacene-12aβ,17-diol) is a novel DOP receptor agonist inducing analgesia and antidepressant effects in mice. Here, we have assessed KNT-127 for (i) analgesia against chronic inflammatory pain; (ii) effects on depression, locomotion and DOP receptor internalization; and (iii) for cross-tolerance to analgesic and antidepressant effects of acute treatment by other DOP receptor agonists.

EXPERIMENTAL APPROACH

Inflammatory pain was induced by complete Freund's adjuvant injection into tail or hindpaw, and thermal and mechanical sensitivities were determined in mice. Locomotor and antidepressant-like effects were measured using actimetry and forced swim test respectively. In vivo KNT-127 selectivity and internalization were assessed using DOP receptor knockout mice and knock-in mice expressing fluorescent-tagged DOP receptors. KNT-127 was injected acutely at 0.1-10.0 mg·kg(-1) or administered chronically at 5 mg·kg(-1) daily over 5 days.

KEY RESULTS

Acute treatment with KNT-127 reversed inflammatory hyperalgesia, produced an antidepressant-like effect but induced neither hyperlocomotion nor receptor sequestration. Chronic treatment with KNT-127 induced tolerance and cross-tolerance to SNC80-induced analgesia, but no tolerance to SNC80-evoked hyperlocomotor or antidepressant-like effects.

CONCLUSIONS AND IMPLICATIONS

The DOP receptor agonist KNT-127 induced agonist-specific acute and chronic responses, at both behavioural and cellular levels. It displays activities similar to the other recently reported DOP agonists, AR-M1000390, ADL5747 and ADL5859, and differs from SNC80. SNC80 differs from the other DOP receptor agonists including KNT-127, by exhibiting ligand-biased tolerance at this receptor.

Effect of γ-cyclodextrin as a lyoprotectant for freeze-dried actinidin

Actinidin (ATD) is a cysteine protease found in kiwifruit. It is used to tenderize meat and to enhance the digestion of proteins in the small intestine. However, ATD is unstable during freeze-drying, which alters its bioactivity. It is well known that sugars have the ability to protect proteins from the stress of freeze-drying. In this study, we investigated the protective effect of various saccharides on the stability of ATD during freeze-drying. The ATD activities of the samples containing γ-cyclodextrin (CyD) showed only a small decrease, and compared with trehalose and sucrose, γ-CyD was a more effective stabilizer for ATD. Secondary structural changes in freeze-dried ATD were observed by circular dichroism spectroscopy and compared with the changes in stabilized samples. There was a close relationship between the α-helix content and the stabilization. The sugars stabilized the protein by suppressing the changes in the α-helix. Fourier transform infrared spectroscopy measurement showed that the amide I band of ATD with γ-CyD was shifted to a lower wavenumber compared with other sugars. Therefore, stronger hydrogen bonds may be formed between ATD and γ-CyD than between ATD and other sugars. The suppression of changes in the protein secondary structure accompanying the formation of hydrogen bonding between the protein and the sugar also contributed to the protective effect of the sugars.

Transcriptional analysis of micro-dissected articular cartilage in post-traumatic murine osteoarthritis

OBJECTIVE

Identify gene changes in articular cartilage of the medial tibial plateau (MTP) at 2, 4 and 8 weeks after destabilisation of the medial meniscus (DMM) in mice. Compare our data with previously published datasets to ascertain dysregulated pathways and genes in osteoarthritis (OA).

DESIGN

RNA was extracted from the ipsilateral and contralateral MTP cartilage, amplified, labelled and hybridized on Illumina WGv2 microarrays. Results were confirmed by real-time polymerase chain reaction (PCR) for selected genes.

RESULTS

Transcriptional analysis and network reconstruction revealed changes in extracellular matrix and cytoskeletal genes induced by DMM. TGFβ signalling pathway and complement and coagulation cascade genes were regulated at 2 weeks. Fibronectin (Fn1) is a hub in a reconstructed network at 2 weeks. Regulated genes decrease over time. By 8 weeks fibromodulin (Fmod) and tenascin N (Tnn) are the only dysregulated genes present in the DMM operated knees. Comparison with human and rodent published gene sets identified genes overlapping between our array and eight other studies.

CONCLUSIONS

Cartilage contributes a minute percentage to the RNA extracted from the whole joint (<0.2%), yet is sensitive to changes in gene expression post-DMM. The post-DMM transcriptional reprogramming wanes over time dissipating by 8 weeks. Common pathways between published gene sets include focal adhesion, regulation of actin cytoskeleton and TGFβ. Common genes include Jagged 1 (Jag1), Tetraspanin 2 (Tspan2), neuroblastoma, suppression of tumourigenicity 1 (Nbl1) and N-myc downstream regulated gene 2 (Ndrg2). The concomitant genes and pathways we identify may warrant further investigation as biomarkers or modulators of OA.

Sesquiterpenoids from the Roots of Solanum aethiopicum

, 2001 Three new sesquiterpenoids, lubiminoic acid, epilubiminoic acid and aethione, and six known sesquiterpenoids, solavetivone, 3β-hydroxysolavetivone, 13-hydroxysolavetivone, an-hydro-β-rotunol, epilubimin and lubimin, were isolated from roots of S. aethiopicum L. Their structures were elucidated by spectroscopic data.

In vivo imaging of MMP-13 activity in the murine destabilised medial meniscus surgical model of osteoarthritis

OBJECTIVE

To detect and determine disease severity of osteoarthritis (OA) using a probe activated by matrix metalloproteinase-13 (MMP-13) in vivo in the murine destabilised medial meniscus (DMM) surgical model of OA.

DESIGN

We have previously described MMP12ap and MMP13ap, internally quenched fluorescent peptide substrate probes that are activated respectively by MMP-12 and MMP-13. Here we used these probes to follow enzyme activity in vivo in mice knees 4, 6 and 8 weeks following DMM surgery. After in vivo optical imaging, disease severity was determined through traditional histological analysis. The amount of probe activation was analysed for discrimination between DMM, contralateral and sham operated knees, as well as for congruence between activity and histological damage.

RESULTS

There was no specific activation of MMP12ap at the time points observed between sham operated and DMM operated, or their respective contralateral joints. The activation of the MMP13ap in the DMM model was highest 6 weeks after surgery, but was only specific compared against sham surgery 8 weeks after surgery (1.5-fold increase). The activation of MMP13ap correlated with histological damage 6 and 8 weeks after surgery, with correlations of 0.484 (P = 0.0032) and 0.478 respectively (P = 0.0049). This correlation dropped to 0.218 (P = 0.011) if all data were considered.

CONCLUSION

The current MMP-13 activity probe is suitable for the discrimination between DMM and sham or contralateral knees 8 weeks after surgery, when cartilage loss is typified by the appearance of small fissures up to the tidemark, but not earlier. This activity correlates with the histological damage observed.

[A case of superior sulcus tumor treated with carbon ion radiotherapy]

Superior sulcus tumor( SST) is a rare type of lung cancer. Treatment usually consists of surgical resection after chemoradiotherapy. We report a case of a woman in her fifties who underwent carbon ion radiotherapy for SST. The patient complained of left shoulder pain, and imaging studies revealed a 5.2×3.5-cm local solid tumor at the apex of the left lung, invasion to the ribs, and no lymph node swelling. The level of tumor marker, carcinoembryonic antigen (CEA), was 5.7 ng/mL. Needle biopsy specimen revealed adenocarcinoma. The diagnosis was SST, T3N0M0, stage IIB. We did not detect Horner syndrome. Carbon ion radiotherapy at 66 Gy equivalent dose per 10 fractions was administered to the SST site. Subsequently, the tumor size decreased to 4.5×1.9-cm. The adverse effect was Grade 1 skin and pulmonary toxicity. Six months later, Grade 2 left shoulder connective tissue toxicity was observed; it was difficult to differentiate this from tumor recurrence. After 2.5 years from radiotherapy, the patient is free from recurrence. Carbon ion radiotherapy is effective and safe and can be considered as an important treatment option for SST.

Deiodinase 2 upregulation demonstrated in osteoarthritis patients cartilage causes cartilage destruction in tissue-specific transgenic rats

OBJECTIVE

Chondrocyte hypertrophy followed by cartilage destruction is a crucial step for osteoarthritis (OA) development, however, the underlying mechanism remains largely unknown. The objectives of this study are to identify the gene that may cause cartilage hypertrophy and to elucidate its role on OA pathogenesis.

DESIGN

Gene expression profiles of cartilages from OA patients and normal subjects were examined by microarray analysis. Expression of deiodinases, enzymes for regulation of triiodothyronine (T3) biosynthesis, in human and rat articular cartilage (AC) were examined by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Rat ACs and chondrocytes were treated with T3 to investigate its role on chondrocyte hypertrophy and inflammatory reaction. Cartilage-specific Type II deiodinase (DIO2) transgenic rats were generated using bacterial artificial chromosome harboring the entire rat Col2a1 and human DIO2 gene. An experimental OA model was created in the animal to examine the role of DIO2 on cartilage degeneration.

RESULTS

DIO2 is highly expressed in OA patient AC compared to normal control. In rat AC, DIO2 is specifically expressed among deiodinases and dominantly expressed the same as in brown adipose tissue. T3 induces hypertrophic markers in articular chondrocyte and cartilage explant culture, and enhances the effect of IL-1α on induction of cartilage degrading enzymes. Importantly, cartilage-specific DIO2 transgenic rats are more susceptible to knee joint destabilization and develop severe AC destruction.

CONCLUSION

Our findings demonstrate that upregulated expression of DIO2 in OA patient cartilage might be responsible for OA pathogenesis by enhancing the chondrocyte hypertrophy and inflammatory response.

[Chemotherapy-mediated tumor regression in a patient with stage IV stomach small cell cancer]

Gastrointestinal tract endoscopy revealed the presence of a 5-cm-diameter type 3 tumor in the cardiac portion of the stomach. The tumor was chromogranin positive, and stomach small cell cancer was diagnosed by immunostaining and biopsy pathology. S-1+CDDP therapy was administered as the first-line treatment. A switch to S-1 monotherapy was made after the patient experienced grade 4 hyponatremia. However, following 7 courses of therapy the disease had progressed. Second-line chemotherapy of CPT-11+CDDP was initiated and after 2 courses the disease stabilized.

[Fluoropyrimidines with oxaliplatin(L-OHP) as an adjuvant chemotherapy for Stage III colon cancer]

As an adjuvant treatment for Dukes B2 and C colon cancer, adding oxaliplatin (L-OHP) to a regimen of fluorouracil and Leucovorin improved disease-free survival in Western countries. In Japan, however, adjuvant chemotherapy with L-OHP is not commonly used to treat Stage III colon cancer. We report the present condition of adjuvant treatment for colon cancer in our hospital. Between September 2009 and December 2011, 66 patients with Stage III colon cancer were enrolled after curative surgery. The details of adjuvant therapy with fluoropyrimidines with and without L-OHP were explained to the patients. After the explanation, 33.3% of the patients(IIIa: 18.9%, IIIb: 55.5%) selected L-OHP chemotherapy. Regardless of the side effects, adjuvant chemotherapy including L-OHP is expected to protect against cancer recurrence in patients with Stage IIIb colon cancer.

[A case of advanced gastric cancer with Trousseau syndrome and pulmonary embolism]

A 60-year-old man showed symptoms associated with pulmonary embolism and anemia in June 2011, and was subsequently diagnosed with stage IV gastric cancer. Following frequent multiple cerebral infarctions and the development of symptoms, the patient was diagnosed with Trousseau syndrome. A total gastrectomy was performed to control bleeding. After the surgery, oral ingestion became possible. The patient was discharged and a hypodermic injection of heparin was given by the home doctor.

Expression of epidermal growth-factor (EGF), matrix metalloproteinase-9 (mmp-9) and proliferating cell nuclear antigen (pcna) in esophageal cancer

Expression of human epidermal growth factor (EGF) and matrix metalloproteinase-9 (MMP-9/gelatinase B) was examined immunohistochemically in 62 cases of surgically resected esophageal carcinomas, and the correlation between EGF expression and the proliferative activity of the tumors was studied by analysing the number of proliferating cell nuclear antigen (PCNA)-positive cells. Expression of EGF and MMP-9 was observed in 16 (38.1%) and 18 (42.9%) of the 42 superficial carcinomas and 8 (40%) and 14 (70%) of the 20 advanced carcinomas, respectively. The differences in the MMP-9 expression between the superficial carcinomas and the advanced carcinomas was significant (p<0.05). The synchronous expression of EGF and MMP-9 was observed in 15 (24.2%) of 62 carcinomas, i.e. 62.5% of the 24 EGF-positive tumors expressed MMP-9, but there was no statistically significant correlation between the expression of EGF and MMP-9. The relationships between EGF expression and tumor proliferative activity and prognostic factors were investigated. The PCNA grades were significantly higher in tumors with EGF-positive than those with EGF-negative expression (p<0.05) and the EGF expression showed a good correlation between the expression of MMP-9 and vascular invasion (p<0.01). The expression of MMP-9 was stronger in the advanced than the superficial carcinomas and there was a good correlation with vascular invasion (p<0.01). In a follow-up study of 55 patients, those with tumor that expressed MMP-9 or had a high PCNA grade showed a poor prognosis. Taken together, these observations suggest that both EGF and MMP-9 participate in the invasive phenotype in human esophageal carcinoma, but the expression of EGF is not directly related to the expression of MMP-9. Additional growth factors and cytokines may be involved in regulation of MMP-9 expression in this carcinoma.

Vagal-Central Nervous System Interactions Modulate the Feeding Response to Peripheral Enterostatin

Enterostatin selectively inhibits the intake of dietary fat after both peripheral and central administration. We have investigated the role of the hepatic vagus nerve in modulating the peripheral response to enterostatin in Sprague-Dawley rats adapted to a high fat (HF) diet. Intraperitoneal (ip) enterostatin reduced intake of HF diet after overnight starvation. This response was abolished by selective vagal hepatic branch transection. Immunohistochemical techniques were used to identify the location of Fos protein in brain nuclei after ip enterostatin. Fos protein was evident in the nucleus tractus solitarius (NTS), parabrachial, paraventricular and supraoptic nuclei. The pattern of expression of Fos-like immunoreactivity differed from that induced by the lipoprivic agent beta-mercaptoacetate. Transection of the hepatic vagus blocked the central Fos responses to ip enterostatin. We conclude that afferent hepatic vagal nerve activity is required for the feeding response to peripheral enterostatin.

Effect of κ-opioid receptor agonist on the growth of non-small cell lung cancer (NSCLC) cells

BACKGROUND

It is becoming increasingly recognised that opioids are responsible for tumour growth. However, the effects of opioids on tumour growth have been controversial.

METHODS

The effects of κ-opioid receptor (KOR) agonist on the growth of non-small cell lung cancer (NSCLC) cells were assessed by a cell proliferation assay. Western blotting was performed to ascertain the mechanism by which treatment with KOR agonist suppresses tumour growth.

RESULTS

Addition of the selective KOR agonist U50,488H to gefitinib-sensitive (HCC827) and gefitinib-resistant (H1975) NSCLC cells produced a concentration-dependent decrease in their growth. These effects were abolished by co-treatment with the selective KOR antagonist nor-BNI. Furthermore, the growth-inhibitory effect of gefitinib in HCC827 cells was further enhanced by co-treatment with U50,488H. With regard to the inhibition of tumour growth, the addition of U50, 488H to H1975 cells produced a concentration-dependent decrease in phosphorylated-glycogen synthase kinase 3β (p-GSK3β).

CONCLUSION

The present results showed that stimulation of KOR reduces the growth of gefitinib-resistant NSCLC cells through the activation of GSK3β.

[A case of bilateral 3-lung lesion (metastatic and primary tumour, tumourlet) resected simultaneously]

A 70-year-old male patient underwent right nephrectomy for renal clear cell carcinoma. After 8 years an X-ray showed a nodule on the left lung, and CT scan detected it to be a 15 × 12 mm mass in S1+2 segment of the left lung. CT also detected another 15 × 7 mm mass in the right S3 segment. These lesions had a high FDG accumulation. Pre-operative diagnosis is bilateral pulmonary metastases from renal cell carcinoma, and bilateral lung segmentectomy was performed. Left S1+2 resected tumor was histologically clear cell carcinoma by intra-operative examination, then right S3 segmentectomy was done. And that time, small tumor was found in the middle lung lobe, and a wedge resection was performed. These specimens revealed a primary lung carcinoma of right S3, and tumourlet of middle lobe. It is very rare that three different histlogical types of lung tumor were found.

[A case of adenocarcinoma of the esophagogastric junction successfully treated with chemoradiation therapy]

The patient was an 80-year-old female with chief complaint of anemia. She was diagnosed as a type 3 gastric cancer (por/tub2) of the esophagogastric junction by gastrointestinal endoscopy in November 2010. CT scan revealed no distant metastasis and we diagnosed as c-stage II B (T4aN0M0). However, severe COPD was detected by the respiratory function test. Considering her age and respiratory function, we decided that total gastrectomy under general anesthesia was difficult. She was treated with radiation( 50.4 Gy/28 Fr) and the combination chemotherapy of S-1( 80 mg/m², day 1-21) plus low-dose CDDP (6 mg/m², day 1-5, 8-12, 15-19) during her hospitalization, and treated with S-1 mono-therapy as an outpatient. The tumor was reduced and the hemorrhage was not seen though the response was SD. Moreover, she did not experience any adverse event of grade 3 or more. The chemoradiation therapy appears to be effective for patients of adenocarcinoma of the esophagogastric junction.

[A case of advanced transvers colon cancer with inguinal lymph node metastasis]

An 80-year-old woman complaining of a right inguinal induration and pain was performed an inguinal lymph node resection. Histological examination with immnohistochemistry revealed that the lymph node was metastasis of colon carcinoma. With total colonoscopy, she was diagnosed as advanced transvers colon cancer with right inguinal lymph node metastasis. She was performed a right hemi-colectomy. She was dead with peritoneal metastasis of colon cancer 2 years and 1 month later. We report this case that was diagnosed having transverse colon cancer with inguinal lymph node metastasis.

[The cover stent custody case that acknowledged QOL improvement on traffic between trachea and esophagus of esophagus cancer]

The case was a 60-year-old man. The patient with a main complaint of husky voice was introduced by a nearby doctor to our otolaryngology department at the end of August 2009. Because of the wall thickening image of the upper part (Ut domain) esophagus, left infraclavicular lymph node and mediastium lymphadenopathy syndrome observed by head and neck CT, the patient was transferred to surgery department. Squamous cell carcinoma was diagnosed based on the upper part gastrointestinal tract endoscopy showing a type-3 advanced cancer of the upper thoracic esophagus sized 25-30 cm from nostril. The patient was in PD, fever and coughing, though we performed 2 FAP therapies. A chest CT revealed that there was a passage between the trachea and esophagus. Then, radiation therapy( a total of 60 Gy, 2 Gy at a time) was enforced. After the radio therapy, a covered type Ultraflex esophagus stent was inserted due to a fistula, though the tumor was reduced to 6 mm in size. The patient was passed away five months after the stent custody; a solid food intake was possible until just before he died.

[A case of liver tumor diagnosed 5 years after gastrectomy against gastric cancer]

A-62-year-old man with gastric cancer underwent gastrectomy 5 years ago, and an abdominal computed tomography scan detected a 15 mm early enhanced lesion located liver (S8) in 2008. Although primary or metastatic were unclear, we underwent partial hepatectomy( S8) as it was an isolated liver tumor. Pathological finding showed adenocarcinoma, and immunostaining was negative for cytokeratin (CK) 7 and positive for CK20 which was the same in primary gastric cancer, so it was diagnosed liver metastasis of gastric cancer. The patient was living at the time, but he passed away 24 months after hepatectomy. We report herein the case of resectable case of liver tumor 5 years after gastrectomy against gastric cancer.