Dysfunction of CD8 + PD-1 + T cells in type 2 diabetes caused by the impairment of metabolism-immune axis.

The metabolic changes and dysfunction in CD8 + T cells may be involved in tumor progression and susceptibility to virus infection in type 2 diabetes (T2D). In C57BL/6JJcl mice fed with high fat-high sucrose chow (HFS), multifunctionality of CD8 + splenic and tumor-infiltrating lymphocytes (TILs) was impaired and associated with enhanced tumor growth, which were inhibited by metformin. In CD8 + splenic T cells from the HFS mice, glycolysis/basal respiration ratio was significantly reduced and reversed by metformin. In the patients with T2D (DM), multifunctionality of circulating CD8 + PD-1 + T cells stimulated with PMA/ionomycin as well as with HLA-A*24:02 CMV peptide was dampened, while metformin recovered multifunctionality. Both glycolysis and basal respiration were reduced in DM, and glycolysis was increased by metformin. The disturbance of the link between metabolism and immune function in CD8 + PD-1 + T cells in T2D was proved by recovery of antigen-specific and non-specific cytokine production via metformin-mediated increase in glycolytic activity.

Severe Visceral Obesity, Fatty Liver and Diabetes after Orchiectomy for Prostate Cancer.

A 79-year-old man without a history of diabetes underwent orchiectomy for prostate cancer. Eight months after the operation, he suffered severe deterioration of visceral fat deposition, fatty liver and diabetes. Treatment for diabetes with canagliflozin and dulaglutide resulted in improvement in his glycemic control, visceral fat and fatty liver. Visceral fat-dominant deposition, which differs from the typical course after androgen deprivation therapy, may have been associated with severe exacerbation of diabetes and fatty liver. Glycemic management with a sodium glucose cotransporter 2 (SGLT2) inhibitor and glucagon-like peptide (GLP)-1 receptor agonist may help improve the glucose metabolism, visceral fat deposition and fatty liver after orchiectomy.

Chronic kidney disease is associated with carotid atherosclerosis and symptomatic ischaemic stroke.

Objective We aimed to investigate the relationships among chronic kidney disease (CKD), symptomatic ischaemic stroke, and carotid atherosclerosis. Methods We enrolled 455 patients who underwent carotid ultrasonography in our hospital, including 311 patients with symptomatic ischaemic stroke and 144 patients without symptomatic ischaemic stroke. Carotid intima-media thickness (IMT), the rate of internal carotid artery stenosis, and maximal plaque size were evaluated. Results The mean age of the patients was 68.5 ± 11.0 years and the mean estimated glomerular filtration rate (eGFR) was 68.8 ± 18.2 mL/min/1.73 m2. After adjustment for cardiovascular risk factors, the mean IMT was significantly higher in patients with CKD than in those without CKD. The IMT and eGFR were negatively correlated in patients with stroke (r = -0.169). Multiple logistic regression analyses showed that mean IMT, plaque size, and internal carotid artery stenosis were significant determinants of symptomatic ischaemic stroke after adjustment of multivariate risk factors. Furthermore, the eGFR was a negative determinant of symptomatic ischaemic stroke after adjusting for classical risk factors (odds ratio [95% confidence interval] = 0.868 [0.769-0.979]). Conclusion CKD might be associated with the carotid atherosclerosis and symptomatic ischaemic stroke.

Dipeptidyl peptidase-4 inhibitor ameliorates early renal injury through its anti-inflammatory action in a rat model of type 1 diabetes.

INTRODUCTION: Dipeptidyl peptidase-4 (DPP-4) inhibitors are incretin-based drugs in patients with type 2 diabetes. In our previous study, we showed that glucagon-like peptide-1 (GLP-1) receptor agonist has reno-protective effects through anti-inflammatory action. The mechanism of action of DPP-4 inhibitor is different from that of GLP-1 receptor agonists. It is not obvious whether DPP-4 inhibitor prevents the exacerbation of diabetic nephropathy through anti-inflammatory effects besides lowering blood glucose or not. The purpose of this study is to clarify the reno-protective effects of DPP-4 inhibitor through anti-inflammatory actions in the early diabetic nephropathy. MATERIALS AND METHODS: Five-week-old male Sprague-Dawley (SD) rats were divided into three groups; non-diabetes, diabetes and diabetes treated with DPP-4 inhibitor (PKF275-055; 3 mg/kg/day). PKF275-055 was administered orally for 8 weeks. RESULTS: PKF275-055 increased the serum active GLP-1 concentration and the production of urinary cyclic AMP. PKF275-055 decreased urinary albumin excretion and ameliorated histological change of diabetic nephropathy. Macrophage infiltration was inhibited, and inflammatory molecules were down-regulated by PKF275-055 in the glomeruli. In addition, nuclear factor-κB (NF-κB) activity was suppressed in the kidney. CONCLUSIONS: These results indicate that DPP-4 inhibitor, PKF275-055, have reno-protective effects through anti-inflammatory action in the early stage of diabetic nephropathy. The endogenous biological active GLP-1 might be beneficial on diabetic nephropathy besides lowering blood glucose.

Combination therapy with an angiotensin-converting-enzyme inhibitor and an angiotensin II receptor antagonist ameliorates microinflammation and oxidative stress in patients with diabetic nephropathy.

AIMS/INTRODUCTION: Recent studies have pointed to the effectiveness of combination therapy with an angiotensin-converting-enzyme inhibitor (ACEI) and an angiotensin receptor blocker (ARB) for diabetic nephropathy. However, some controversy over this combination treatment remains and the mechanisms underlying its renoprotective effects have not been fully clarified. Therefore, we compared the renoprotective effects of imidapril (ACEI) and losartan (ARB) combination therapy with losartan monotherapy in patients with diabetic nephropathy. We also compared the anti-inflammatory and anti-oxidative stress effects of these two treatments. MATERIALS AND METHODS: A total of 32 Japanese patients with type 2 diabetes and nephropathy were enrolled. Patients were randomized to either 100 mg/day losartan (n = 16) or 50 mg/day losartan plus 5 mg/day imidapril (n = 16). We evaluated clinical parameters, serum concentrations of high-sensitivity C-reactive protein (hs-CRP), soluble intercellular adhesion molecule-1 (sICAM-1), interleukin-18 (IL-18) and monocyte chemotactic protein-1 (MCP-1), and the urinary concentrations of IL-18, MCP-1 and 8-hydroxy-2'-deoxyguanosine (8-OHdG) at 24 and 48 weeks after starting treatment. RESULTS: Blood pressure was not significantly different between the two groups. The serum levels of hs-CRP, sICAM-1 and IL-18, as well as urinary excretion of albumin, IL-18 and 8-OHdG decreased significantly in the combination therapy group at 48 weeks. The percent decreases in serum IL-18 concentrations and urinary IL-18 and 8-OHdG were significantly greater in the combination therapy group than in the monotherapy group. CONCLUSIONS: Combination therapy with an ACEI and an ARB could be beneficial for treating diabetic nephropathy through its anti-inflammatory and anti-oxidative stress effects.

Phenotypic change of macrophages in the progression of diabetic nephropathy; sialoadhesin-positive activated macrophages are increased in diabetic kidney.

BACKGROUND: Inflammatory process is involved in pathogenesis of diabetic nephropathy, although the activation and phenotypic change of macrophages in diabetic kidney has remained unclear. Sialoadhesin is a macrophage adhesion molecule containing 17 extracellular immunoglobulin-like domains, and is an I-type lectin which binds to sialic acid ligands expressed on hematopoietic cells. The aim of this study is to clarify the activation and phenotypic change of macrophages in the progression of diabetic nephropathy. METHODS: We examined the expression of surface markers for pan-macrophages, resident macrophages, sialoadhesin, major histocompatibility complex class II and α-smooth muscle actin in the glomeruli of diabetic rats using immunohistochemistry at 0, 1, 4, 12, and 24 weeks after induction of diabetes by streptozotocin. Expression of type IV collagen and the change of mesangial matrix area were also measured. The mechanism for up-regulated expression of sialoadhesin on macrophages was evaluated in vitro. RESULTS: The number of macrophages was increased in diabetic glomeruli at 1 month after induction of diabetes and the increased number was maintained until 6 months. On the other hand, sialoadhesin-positive macrophages were increased during the late stage of diabetes concomitantly with the increase of α-smooth muscle actin-positive mesangial cells, mesangial matrix area and type IV collagen. Gene expression of sialoadhesin was induced by stimulation with interleukin (IL)-1ß and tumor necrosis factor-α but not with IL-4, transforming growth factor-ß and high glucose in cultured human macrophages. CONCLUSION: The present findings suggest that sialoadhesin-positive macrophages may contribute to the progression of diabetic nephropathy.

Cholecystokinin plays a novel protective role in diabetic kidney through anti-inflammatory actions on macrophage: anti-inflammatory effect of cholecystokinin.

Inflammatory process is involved in the pathogenesis of diabetic nephropathy. In this article, we show that cholecystokinin (CCK) is expressed in the kidney and exerts renoprotective effects through its anti-inflammatory actions. DNA microarray showed that CCK was upregulated in the kidney of diabetic wild-type (WT) mice but not in diabetic intracellular adhesion molecule-1 knockout mice. We induced diabetes in CCK-1 receptor (CCK-1R) and CCK-2R double-knockout (CCK-1R(-/-),-2R(-/-)) mice, and furthermore, we performed a bone marrow transplantation study using CCK-1R(-/-) mice to determine the role of CCK-1R on macrophages in the diabetic kidney. Diabetic CCK-1R(-/-),-2R(-/-) mice revealed enhanced albuminuria and inflammation in the kidney compared with diabetic WT mice. In addition, diabetic WT mice with CCK-1R(-/-) bone marrow-derived cells developed more albuminuria than diabetic CCK-1R(-/-) mice with WT bone marrow-derived cells. Administration of sulfated cholecystokinin octapeptide (CCK-8S) ameliorated albuminuria, podocyte loss, expression of proinflammatory genes, and infiltration of macrophages in the kidneys of diabetic rats. Furthermore, CCK-8S inhibited both expression of tumor necrosis factor-α and chemotaxis in cultured THP-1 cells. These results suggest that CCK suppresses the activation of macrophage and expression of proinflammatory genes in diabetic kidney. Our findings may provide a novel strategy of therapy for the early stage of diabetic nephropathy.

P-selectin glycoprotein ligand-1 deficiency is protective against obesity-related insulin resistance.

OBJECTIVE: An inflammatory process is involved in the mechanism of obesity-related insulin resistance. Recent studies indicate that monocyte chemoattractant protein-1 (MCP-1) is a major chemokine that promotes monocyte infiltration into adipose tissues; however, the adhesion pathway in adipose tissues remains unclear. We aimed to clarify the adhesion molecules that mediate monocyte infiltration into adipose tissue. RESEARCH DESIGN AND METHODS: We used a DNA microarray to compare the gene expression profiles in epididymal white adipose tissues (eWAT) between db/db mice and C57/BL6 mice each fed a high-fat diet (HFD) or a low-fat diet (LFD). We investigated the change of insulin resistance and inflammation in eWAT in P-selectin glycoprotein ligand-1 (PSGL-1) homozygous knockout (PSGL-1⁻(/)⁻) mice compared with wild-type (WT) mice fed HFD. RESULTS: DNA microarray analysis revealed that PSGL-1, a major ligand for selectins, is upregulated in eWAT from both db/db mice and WT mice fed HFD. Quantitative real-time RT-PCR and immunohistochemistry showed that PSGL-1 is expressed on both endothelial cells and macrophages in eWAT of obese mice. PSGL-1⁻(/)⁻ mice fed HFD showed a remarkable reduction of macrophage accumulation and expression of proinflammatory genes, including MCP-1 in eWAT. Moreover, adipocyte hypertrophy, insulin resistance, lipid metabolism, and hepatic fatty change were improved in PSGL-1⁻(/) ⁻mice compared with WT mice fed HFD. CONCLUSIONS: These results indicate that PSGL-1 is a crucial adhesion molecule for the recruitment of monocytes into adipose tissues in obese mice, making it a candidate for a novel therapeutic target for the prevention of obesity-related insulin resistance.

Microinflammation is a common risk factor for progression of nephropathy and atherosclerosis in Japanese patients with type 2 diabetes.

AIM: This study aimed to evaluate the change of serum levels of proinflammatory molecules in patients with type 2 diabetes and clarify the involvement of these molecules in diabetic nephropathy and atherosclerosis. METHODS: Sixty-six Japanese type 2 diabetic patients (T2DM) and 39 healthy control subjects were enrolled. We assessed clinical parameters, urinary albumin excretion rate (AER), brachial-ankle pulse wave velocity (baPWV), intima media thickness (IMT) and serum levels of proinflammatory molecules. RESULTS: Serum levels of IL-6, IP-10 and MCP-1 were significantly higher in T2DM than in control subjects. In T2DM, serum levels of high-sensitivity (hs) CRP, IP-10, hsTNF-alpha, VCAM-1 and E-selectin were positively correlated with AER. Serum levels of IP-10, hsTNF-alpha and VCAM-1 were positively correlated with baPWV. Serum levels of hsCRP, IL-6, IP-10 and hsTNF-alpha were positively correlated with IMT. Multiple linear regression analysis revealed that serum levels of hsTNF-alpha were independently associated with AER (beta=0.235, P=0.038) and serum levels of IP-10 were independently associated with baPWV (beta=0.209, P=0.047) and IMT (beta=0.303, P=0.032). CONCLUSION: Our results suggest that low-grade inflammation, microinflammation, may be a common risk factor for diabetic nephropathy and atherosclerosis in Japanese type 2 diabetic patients.