Engineered Cartilage Maturation Regulates Cytokine Production and Interleukin-1β Response

Background  

Because the injured joint has an actively inflammatory environment, the survival and repair potential of cartilage grafts may be influenced by inflammatory processes. Understanding the interactions of those processes with the graft may lead to concepts for pharmacologic or surgical solutions allowing improved cartilage repair.     

Expression of Mammalian P1 Protamine Gene

Expression of Mammalian P1 Protamine Gene     

Therapeutic implications of the TGF-β system

This review considers the various roles of the TGF- system in mammary carcinogenesis, tumor progression, and cellular responses to therapeutic measures. The paradigm that has evolved from the work of many investigators suggests that loss of tumor cell responsiveness to the effects of TGF- can result in a crucial shift in the net effect of TGF- within the context of the tumor-host interaction. Principal elements of host-tumor interactions in which this shift may play out, including immune suppression, angiogenesis, and modification of the surrounding extracellular matrix by tumor cells, are potentially amenable to manipulation. Additional effects of TGF-, such as suggested by reports of its ability to alter the drug resistance of tumor cells and the drug sensitivity of normal tissues, suggest that appropriate molecular intervention designed to affect the TGF- system might constitute an effective therapeutic strategy.     

Evaluation of the Role of the SQSTM1 Gene in Sporadic Belgian Patients with Paget’s Disease

A positional cloning effort in French Canadian families with Pagets disease of bone (PDB) resulted in the identification of a mutation in the sequestosome1 (SQSTM1) gene in a subset of both familial and sporadic PDB cases. This was confirmed in samples of mainly United Kingdom (UK) origin. In this study, we performed both mutation analysis and association studies in order to evaluate the role of this gene in a collection of isolated Belgian PDB patients. A mutation in the SQSTM1 gene was found in only 6 of 111 patients (5.4%). In all cases it involves the P392L mutation, previously shown to be common in both familial and sporadic cases. To perform association studies, we selected 8 single nucleotide polymorphisms (SNPs) and looked for linkage disequilibrium (LD) between these. Haplotype analysis indicated that typing of 3 Tag SNPs (IVS1+633A/C, IVS5–23A/G, and 976A/G) enables us to identify the most common haplotypes. Association studies for the 3 selected SNPs, based on 105 PDB cases without a SQSTM1 mutation and 159 control individuals, did not support a possible influence of natural variants in the SQSTM1 gene either on the pathogenesis of PDB or on the disease severity. In conclusion, our study confirms that the P392L mutation is a recurrent mutation causing PDB in different populations. We were not able to show an association between SQSTM1 polymorphisms and PDB in our population but this clearly needs to be extended to other populations. The presented identification of haplotype Tag SNPs will be of major help for such studies.     

Which Gene is a Dominant Predictor of Response During FOLFOX Chemotherapy for the Treatment of Metastatic Colorectal Cancer, the MTHFR or XRCC1 Gene?

Background Combination chemotherapy using oxaliplatin, 5-fluorouracil and folinic acid (FOLFOX) is known to be effective in the treatment of metastatic colon cancer. Genes regulating the actions of 5-fluorouracil and oxaliplatin have been identified, but precisely which gene is dominant has not yet been determined. The aim of the investigation reported here was to identify which gene polymorphism is a dominant factor in FOLFOX chemotherapy–the methylenetetrahydrofolate reductase (MTHFR) gene for 5-fluorouracil or the X-ray cross-complementing1 (XRCC1) gene for oxaliplatin.Methods Paraffin-embedded tissues from 54 patients with unresectable metastases from colorectal cancer who had undergone chemotherapy with the FOLFOX regimen were analyzed for MTHFR polymorphisms in the MTHFR gene (677C➔T, Ala➔Val mutation) and XRCC1 gene (Arg➔Gln substitution in exon 10). Response rates and survivals were compared by types of polymorphism.Results Analyses of the patterns of MTHFR polymorphism revealed that 29.6% of the patients showed no mutation, 51.6% showed heterozygous mutations, and 11.8% showed homozygous mutations. Analyses of the XRCC1 polymorphism revealed that 60.8% of the patients showed no mutation, 31.4% showed heterozygous mutations, and 7.8% showed homozygous mutations. After four cycles of chemotherapy, 3.7% showed a complete response, 57.4% showed a partial response (PD) or stable disease, and 38.9% showed PD. The MTHFR polymorphism was not significant in predicting response and 30-month-survival (P > .1), whereas the XRCC1 polymorphism was a significant prognostic factor for both response (P = .038) and survival (P = .011).Conclusions We found a higher rate of mutations in the MTHFR gene than in the XRCC1 gene in Korean colorectal cancer patients. Response to FOLFOX was better in the patient group with mutations for MTHFR and worse in the patient group with mutations for XRCC1. However, only the XRCC1 polymorphism was a significant prognostic factor for the response to FOLFOX chemotherapy and short-term survival.     

Systemic liberation of interleukin-1β and interleukin-1 receptor antagonist in the perioperative phase of liver transplantation

We measured systemic serum levels of interleukin-1 receptor antagonist (IL-1ra), interleukin-1 (IL-1), tumor necrosis factor (TNF-), and interleukin-6 (IL-6) during the preoperative, anhepatic, and postreperfusional phases up to the 7th postoperative day in 60 patients undergoing orthotopic liver transplantation (LTx). In contrast to IL-1, IL-1ra, TNF-, and IL-6 showed a significant elevation in relation to the early phase after reperfusion, while TNF- displayed a high grade of scatter. In addition, IL-1ra levels were significantly elevated during the anhepatic phase. Maximum serum levels were found at 15 min after reperfusion, 120 min after reperfusion, and on the 1st postoperative day, respectively. Serum levels decreased considerably at 24 h and 7 days after reperfusion. The comparative monitoring of systemic cytokine and cytokine antagonist levels, in particular the liberation of IL-1ra and IL-6 may provide useful parameters for the development of new liver preservation theories for LTx.     

Analysis of polymorphisms in the promoter region of interleukin-1β by restriction fragment length polymorphism-PCR

Objective: To investigate the frequencies of -1470, -511 and -31 single nucleotide polymorphisms (SNPs) in the promoter of IL-1β and its haplotype constitution in Chongqing population. Methods: One hundred and twelve healthy Chongqing people were enrolled in this study. Polymorphisms at -1470 (G to C), -511 (T to C) and -31(C to T) of IL-1β were genotyped with the method of restriction fragment length polymorphism ( RFLP ). Haplotype frequencies were analyzed by Adequine software. Results: Frequencies of IL-1β -1470, -511 and -31 SNPs were 41.67%, 50% and 45.33%, respectively. Genotype frequencies of -1470 locus were 39.81%, 37.04% and 23.15% for G/G, G/C and C/C respectively. As for T-511C SNP, genotype frequencies of T/T, T/C and C/C were 29.91%, 40.18% and 29.91%, respectively. Genotyping results of C/C, C/T, and T/T of -31 locus were 35.51%, 38.32 % and 26.71% respectively. Haplotype analysis found that there were mainly three haplotypes constituted by three SNPs, ie., G-T-C, C-T-Cand G-C-T. Conclusions: Polymorphisms exist in the promoter of IL-1β in Chongqing population. Three SNPs locate in the same haplotype block. Key words : lnterleukin-1 ; Polymorphism, restriction fragment length ; Polymorphisms, single nucleotide; Genotype; Haplotypes.     

IL-1β Drives Production of FGF-23 at the Onset of Chronic Kidney Disease in Mice

FGF-23 has arisen as an early biomarker of renal dysfunction, but at the onset of chronic kidney disease (CKD), data suggest that FGF-23 may be produced independently of the parathyroid hormone (PTH), 1,25(OH)₂-vitamin D₃ signaling axis. Iron status is inversely correlated to the level of circulating FGF-23, and improvement in iron bioavailability within patients correlates with a decrease in FGF-23. Alternately, recent evidence also supports a regulatory role of inflammatory cytokines in the modulation of FGF-23 expression. To determine the identity of the signal from the kidney-inducing upregulation of osteocytic FGF-23 at the onset of CKD, we utilized a mouse model of congenital CKD that fails to properly mature the glomerular capillary tuft. We profiled the sequential presentation of indicators of renal dysfunction, phosphate imbalance, and iron bioavailability and transport to identify the events that initiate osteocytic production of FGF-23 during the onset of CKD. We report here that elevations in circulating intact-FGF-23 coincide with the earliest indicators of renal dysfunction (P14), and precede changes in serum phosphate or iron homeostasis. Serum PTH was also not changed within the first month. Instead, production of the inflammatory protein IL-1β from the kidney and systemic elevation of it in the circulation matched the induction of FGF-23. IL-1β's ability to induce FGF-23 was confirmed on bone chips in culture and within mice in vivo. Furthermore, neutralizing antibody to IL-1β blocked FGF-23 expression in both our congenital model of CKD and a second nephrotoxic serum-mediated model. We conclude that early CKD resembles a situation of primary FGF-23 excess mediated by inflammation. These findings do not preclude that altered mineral availability or anemia can later modulate FGF-23 levels but find that in early CKD they are not the driving stimulus for the initial upregulation of FGF-23. © 2020 American Society for Bone and Mineral Research.     

Elevation of urinary IL-1β levels during transplant associated nephropathy in rat model of the nephrotic syndrome

A recurrence of nephrotic syndrome is a well-known phenomenon in patients who receive kidney transplantation. In this study, we attempt to establish a rat model of recurrent nephrotic change after renal transplantation using puromycin aminonucleoside (PA) induced nephrotic rats. We then examine the mechanism leading to recurrence. Female Sprague-Dawley rats (8 weeks) were divided into four groups: group A, allogenic renal transplantation of a normal kidney to PA-induced nephrotic rats; group B, PA injection only as a nephrotic control; group C, allogenic transplantation of a normal kidney to rats receiving a saline injection; group D, rats receiving only a saline injection. The serum and urinary levels of protein, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-2 and interferon (IFN)-gamma were measured. The cytokine levels were assessed by performing enzyme-linked immunosorbent assays. Six days after renal transplantation, the kidneys were excised, tissue sections were stained with hematoxylin-eosin and the specimens were studied for pathological alterations. The urinary protein levels and the histological results of protein casts in renal tubules of the autologous kidneys of the nephrotic rats and the transplanted kidneys confirmed the recurrence of nephrotic syndrome in the transplanted kidney. After renal transplantation, urinary protein and IL-1beta levels were significantly elevated in recurrent transplanted kidney groups compared with those in the control groups, while the TNF-alpha, IL-2, and IFN-gamma levels were not elevated. In addition, serum levels of TNFalpha and IL-1beta were not elevated. These results suggested that IL-1beta may relate to the recurrent nephropathy in the transplanted kidney in the nephrotic rat.     

Nonmuscle Myosin II Regulates the Morphogenesis of Metanephric Mesenchyme–Derived Immature Nephrons

The kidney develops from reciprocal interactions between the metanephric mesenchyme and ureteric bud. The mesenchyme transforms into epithelia and forms complicated nephron structures, whereas the ureteric bud extends its pre-existing epithelial ducts. Although the roles are well established for extracellular stimuli, such as Wnt and Notch, it is unclear how the intracellular cytoskeleton regulates these morphogenetic processes. Myh9 and Myh10 encode nonmuscle myosin II heavy chains, and Myh9 mutations in humans are implicated in congenital kidney diseases and focal segmental glomerulosclerosis in adults. Here, we analyzed the roles of Myh9 and Myh10 in the developing kidney. Ureteric bud-specific depletion of Myh9 resulted in no apparent phenotypes, whereas mesenchyme-specific Myh9 deletion caused proximal tubule dilations and renal failure. Mesenchyme-specific Myh9/Myh10 mutant mice died shortly after birth and showed a severe defect in nephron formation. The nascent mutant nephrons failed to form a continuous lumen, which likely resulted from impaired apical constriction of the elongating tubules. In addition, nephron progenitors lacking Myh9/Myh10 or the possible interactor Kif26b were less condensed at midgestation and reduced at birth. Taken together, nonmuscle myosin II regulates the morphogenesis of immature nephrons derived from the metanephric mesenchyme and the maintenance of nephron progenitors. Our data also suggest that Myh9 deletion in mice results in failure to maintain renal tubules but not in glomerulosclerosis.     

γ-Aminobutyric Acid Regulates Both the Survival and Replication of Human β-Cells

γ-Aminobutyric acid (GABA) has been shown to inhibit apoptosis of rodent β-cells in vitro. In this study, we show that activation of GABA_A receptors (GABA_A-Rs) or GABA_B-Rs significantly inhibits oxidative stress–related β-cell apoptosis and preserves pancreatic β-cells in streptozotocin-rendered hyperglycemic mice. Moreover, treatment with GABA, or a GABA_A-R– or GABA_B-R–specific agonist, inhibited human β-cell apoptosis following islet transplantation into NOD/scid mice. Accordingly, activation of GABA_A-Rs and/or GABA_B-Rs may be a useful adjunct therapy for human islet transplantation. GABA-R agonists also promoted β-cell replication in hyperglycemic mice. While a number of agents can promote rodent β-cell replication, most fail to provide similar activities with human β-cells. In this study, we show that GABA administration promotes β-cell replication and functional recovery in human islets following implantation into NOD/scid mice. Human β-cell replication was induced by both GABA_A-R and GABA_B-R activation. Hence, GABA regulates both the survival and replication of human β-cells. These actions, together with the anti-inflammatory properties of GABA, suggest that modulation of peripheral GABA-Rs may represent a promising new therapeutic strategy for improving β-cell survival following human islet transplantation and increasing β-cells in patients with diabetes.A central focus of research in the type 1 diabetes (T1D) field is to develop ways to safely improve β-cell survival and function and promote their replication. The addition of γ-aminobutyric acid (GABA) or the GABA_B receptor (GABA_B-R)–specific agonist baclofen to culture media has been shown to inhibit β-cell apoptosis in cultured rodent cell lines and islets (1,2). It remains to be determined whether GABA treatment can inhibit mouse β-cell apoptosis in vivo or, more importantly, whether it can protect human β-cells from stress-induced apoptosis. If GABA can inhibit human β-cell apoptosis, elucidating whether this effect is mediated through the G-protein–coupled GABA_B-Rs, and/or the chloride channel GABA_A-Rs will enable more specific drug targeting.GABA can promote neurogenesis and neuronal proliferation and is a neuronal survival factor (3–8). GABA has also been shown to promote rodent β-cell replication (1,2). Those studies, however, differentially pointed to GABA_A-Rs or GABA_B-Rs as modulators of GABA’s effects, making it important to clarify whether one or both types of GABA receptors modulate rodent β-cell replication. While a number of mitogens and growth factors can promote rodent β-cell replication, most fail to promote human β-cell replication (reviewed in refs. 9,10). Therefore, a key question is whether GABA can promote human β-cell replication. Even a small amount of GABA-induced human β-cell replication may be clinically useful by lowering insulin requirements and reducing the risk for long-term complications in T1D patients (11).