Molecular Signatures of Mitochondrial Complexes Involved in Alzheimer's Disease via Oxidative Phosphorylation and Retrograde Endocannabinoid Signaling Pathways.

Objective: The inability to intervene in Alzheimer's disease (AD) forces the search for promising gene-targeted therapies. This study was aimed at exploring molecular signatures and mechanistic pathways to improve the diagnosis and treatment of AD. Methods: Microarray datasets were collected to filter differentially expressed genes (DEGs) between AD and nondementia controls. Weight gene correlation network analysis (WGCNA) was employed to analyze the correlation of coexpression modules with AD phenotype. A global regulatory network was established and then visualized using Cytoscape software to determine hub genes and their mechanistic pathways. Receiver operating characteristic (ROC) analysis was conducted to estimate the diagnostic performance of hub genes in AD prediction. Results: A total of 2,163 DEGs from 13,049 background genes were screened in AD relative to nondementia controls. Among the six coexpression modules constructed by WGCNA, DEGs of the key modules with the strongest correlation with AD were extracted to build a global regulatory network. According to the Maximal Clique Centrality (MCC) method, five hub genes associated with mitochondrial complexes were chosen. Further pathway enrichment analysis of hub genes, such as oxidative phosphorylation and retrograde endocannabinoid signaling, was identified. According to the area under the curve (AUC) of about 70%, each hub gene exhibited a good diagnostic performance in predicting AD. Conclusions: Our findings highlight the perturbation of mitochondrial complexes underlying AD onset, which is mediated by molecular signatures involved in oxidative phosphorylation (COX5A, NDUFAB1, SDHB, UQCRC2, and UQCRFS1) and retrograde endocannabinoid signaling (NDUFAB1) pathways.

Effects of anti-diabetic drugs on sarcopenia: Best treatment options for elderly patients with type 2 diabetes mellitus and sarcopenia.

Human life expectancy increases as society becomes more developed. This increased life expectancy poses challenges associated with the rapid aging of the population. Sarcopenia, an age-related disease, has become a worldwide health issue. Patients with sarcopenia experience decreases in muscle mass and function, becoming frail and eventually bedridden. Type 2 diabetes mellitus (T2DM) is also a major health issue; the incidence of T2DM increases with aging. T2DM is associated with reduced muscle strength and poor muscle quality and may contribute to acceleration of the aging process, augmenting age-related sarcopenia. Recent studies indicate that elderly patients with diabetes are at an increased risk for sarcopenia. Therefore, these older diabetic patients with sarcopenia need specific anti-diabetic therapies targeting not only glycemic control but also sarcopenia, with the goal of preventing sarcopenia in pre-sarcopenic patients. Presently, various types of hypoglycemic drugs are available, but which hypoglycemic drugs are better suited for geriatric T2DM patients with sarcopenia remains undetermined. In this review, we discuss the association between diabetes and sarcopenia in geriatric patients, and how anti-diabetic drugs may influence sarcopenia outcomes. This review will guide clinical workers in the selection of drugs best suited for this patient population.

Molecular identification of protein kinase C beta in Alzheimer's disease.

The purpose of this study was to investigate the potential roles of protein kinase C beta (PRKCB) in the pathogenesis of Alzheimer's disease (AD). We identified 2,254 differentially expressed genes from 19,245 background genes in AD versus control as well as PRKCB-low versus high group. Five co-expression modules were constructed by weight gene correlation network analysis. Among them, the 1,222 genes of the turquoise module had the strongest relation to AD and those with low PRKCB expression, which were enriched in apoptosis, axon guidance, gap junction, Fc gamma receptor (FcγR)-mediated phagocytosis, mitogen-activated protein kinase (MAPK) and vascular endothelial growth factor (VEGF) signaling pathways. The intersection pathways of PRKCB in AD were determined, including gap junction, FcγR-mediated phagocytosis, MAPK and VEGF signaling pathways. Based on the performance evaluation of the area under the curve of 75.3%, PRKCB could accurately predict the onset of AD. Therefore, low expressions of PRKCB was a potential causative factor of AD, which might be involved in gap junction, FcγR-mediated phagocytosis, MAPK and VEGF signaling pathways.

Risk Factors for Sarcopenia in the Elderly with Type 2 Diabetes Mellitus and the Effect of Metformin.

AIMS: Sarcopenia is a common condition in older individuals, especially in the elderly with type 2 diabetes mellitus (T2DM). The aim of the present study was to examine the risk factors for sarcopenia in elderly individuals with T2DM and the effects of metformin. METHODS: A total of 1732 elderly with T2DM were recruited to this cross-sectional observational study, and we analyzed the data using logistic regression analyses. Skeletal muscle mass, grip strength, and usual gait speed were measured to diagnose sarcopenia according to the criteria of the Asian Working Group for Sarcopenia, combined with expert consensus on sarcopenia in China. RESULTS: The overall prevalence of sarcopenia was 10.37% of the participants. In the multivariate analysis, sex, age, educational level, and BMI were risk factors for sarcopenia, with women more likely to develop sarcopenia relative to men (OR = 2.539, 95% CI = 1.475-4.371; P < 0.05). We observed that sarcopenia increased with age and decreased with increasing BMI and educational level (P < 0.05). Participants who took metformin alone or combined with other drugs exhibited a lower risk for sarcopenia than those who took no medication (OR = 0.510, 95% CI = 0.288-0.904 and OR = 0.398, 95% CI = 0.225-0.702, respectively; P < 0.05). CONCLUSIONS: We showed that being female and at an older age, lower educational level, and lower BMI were risk factors for sarcopenia in elderly T2DM and that metformin acted as a protective agent against sarcopenia in these patients.

Risk factors for depression in elderly diabetic patients and the effect of metformin on the condition.

BACKGROUND: At present, only a few studies have focused on the risk factors for depression in elderly diabetic patients, and there is little evidence for the effect of metformin in depressed elderly patients with diabetes than on its effect on blood glucose. The aim of the current work was to study the risk factors for depression in elderly diabetic patients and to ascertain the effects of metformin on the depressive state. METHODS: We initiated a 1:4 matched case-control study. The case group comprised 110 elderly diabetic patients with depression from nine communities in Shenyang in 2017. The control group comprised 440 non-depressed elderly diabetic patients from the same communities, which were matched by gender and age (± 2 years of age) with the case group. Depression was measured using the Geriatric Depression Scale-15, and we performed matched univariate and multivariate logistic regression analyses. RESULTS: In the multivariate analysis, overweight status, poor physical capabilities and low activity level, and the presence of more than two additional illnesses were risk factors for depression in elderly patients with diabetes. For these risk factors, the adjusted ORs (all P < 0.05) were as follows: an adjusted OR of 2.031 and 95% CI of 1.180-3.495; an adjusted OR of 2.342 and 95% CI of 1.465-3.743; and an adjusted OR of 5.350 and 95% CI of 2.222-12.883, respectively. Patients taking metformin had a lower risk of depression than those taking no medication, with an adjusted OR of 0.567 and 95% CI of 0.323-0.997 (P < 0.05). CONCLUSIONS: Overweight status, poor physical capabilities and low activity level, and the presence of more than two additional illnesses were risk factors for depression in elderly diabetic patients, and metformin was a protective factor against depression in elderly diabetic patients.

The Mechanism of miR-192 in Regulating High Glucose-Induced MCP-1 Expression in Rat Glomerular Mesangial Cells.

BACKGROUND: Although the pathogenetic mechanism of Diabetic Kidney Disease (DKD) has not been elucidated, an inflammatory mechanism may be a potential contributor. Monocyte chemotactic protein-1 (MCP-1) is suggested to be implicated in the development of DKD by playing a role in the infiltration of monocyte/macrophage. The aim of this study was to investigate the expression of MCP-1 under high glucose conditions, as well as the effects of microRNA-192 (miR-192) under these conditions, and to study the regulatory mechanism of MCP-1 in DKD. METHODS: Rat glomerular mesangial cells were cultured in high glucose or isotonic mannitol. The messenger RNA(mRNA) expression of miR-192, miR-200b, miR-200c, E-box-binding homeobox 1 (Zeb1), and MCP-1 was then detected by real-time PCR, and the protein expression of Zeb1 and MCP- 1 was assessed by western blotting. The rat mesangial cells were transfected with an miR-192 inhibitor, NC inhibitor , and transfected with siRNA Zeb1, siNC. The cells were then cultured in high glucose to detect the mRNA expression of miR-192, miR-200b, miR-200c, Zeb1, and MCP-1 using realtime PCR, and Zeb1 and MCP-1 protein expression were determined by western blotting. RESULTS: MiR-192, miR-200b, miR-200c, and MCP-1 were overexpressed, whereas Zeb1 was downregulated when cultured in high glucose (P < 0.05). After transfection with an miR-192 inhibitor, the expression of miR-192, miR-200b, miR-200c, and MCP-1 was downregulated, whereas Zeb1 was increased, and these differences were statistically significant (P < 0.05). The observed changes in the expression in the NC inhibitor transfection group were similar to that of non-transfected cell lines. Silencing the expression of Zeb1 resulted in a significant increase in the expression of miR-192, miR- 200b, miR-200c, and MCP-1 (P < 0.05). The observed changes in the SiNC transfection group were similar to those of non-transfected cell lines. CONCLUSIONS: MiR-192 expression was upregulated to increase the expression of inflammatory factor MCP-1 by inhibiting the expression of Zeb1, which was mediated by breaking the regulatory loop of Zeb1 and miR-200b/c in rat mesangial cells cultured in high glucose.

Naringin ameliorates the high glucose-induced rat mesangial cell inflammatory reaction by modulating the NLRP3 Inflammasome.

BACKGROUND: The Nucleotide binding and oligomerization domain-like receptorfamily pyrin domain-containing 3 (NLRP3)-inflammasome plays an important role in various diseases, including a variety of kidney diseases. Naringin exhibits anti-inflammatory and anti-oxidation effects among others, but its specific mechanisms are not clear. We investigated the expression of the NLRP3-inflammasome under high-glucose conditions, assessed the effects of naringin on that process, and further elucidated the role of naringin in the pathogenesis of diabetic kidney disease(DKD). METHODS: To assess the therapeutic potential of naringin and the mechanisms involved, we cultured rat glomerular mesangial cells and grouped them according to different glucose concentrations, different action times, different concentrations of MCC950, and different concentrations of naringin.The cell proliferation was measured by MTT assay. The expression of Interleukin-1ß(IL-1ß) and Interleukin18 (IL-18) in the cell supernatant were detected by ELISA. The expression and activity of NLPR3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) and Caspase-1 were detected by Western Blot. RESULTS: The expressions of NLRP3, ASC, caspase-1, IL-1ß, and IL-18 in rat glomerular mesangial cells were significantly higher in the high glucose (HG) group than in the control normal glucose (NG) group and exhibited time-dependence activity. The expression levels of NLRP3, caspase-1, IL-1ß, and IL-18 in different treatment groups were significantly lower compared with the HG group after 48 h of MCC950 pre-treatment (p < 0.05). Pre-treatment with naringin produced the same results. Naringin also inhibited the proliferation of cells. CONCLUSIONS: The NLRP3-inflammasome potentially plays a role in the process of activation and inflammation of glomerular mesangial cells as induced by high-glucose conditions. Naringin inhibited the proliferation of cells that were induced by high glucose. Further, it reduced the expression of inflammatory factors that are mediated by NLRP3 through the NLRP3-caspase-1-IL-1ß/IL-18 signaling pathway, which makes naringin a potentially novel treatment for DKD disease.

Naringin Alleviates Diabetic Kidney Disease through Inhibiting Oxidative Stress and Inflammatory Reaction.

Naringin, a flavanone glycoside extracted from Citrus grandis Osbeck, has a wide range of pharmacological effects. In the present study we aimed at demonstrating the protective effect of naringin against diabetic kidney disease (DKD) and elucidating its possible molecular mechanism underlying. The beneficial effect of naringin was assessed in rats with streptozotocin (STZ)-induced diabetes and high glucose-induced HBZY-1 cells. According to our results, first we found that naringin relieved kidney injury, improved renal function and inhibited collagen formation and renal interstitial fibrosis. Second, we confirmed that naringin restrained oxidative stress by activating Nrf2 antioxidant pathway. Moreover, the results suggested that naringin significantly resisted inflammatory reaction by inhibiting NF- κ B signaling pathway. Taken together, our results demonstrate that naringin effectively alleviates DKD, which provide theoretical basis for naringin clinically used to treatment of DKD.

The function of miR-199a-5p/Klotho regulating TLR4/NF-κB p65/NGAL pathways in rat mesangial cells cultured with high glucose and the mechanism.

Anti-aging protein Klotho may confer a renal protective effect via attenuating the nuclear factor-κB (NF-κB) p65 pathways activity. Besides, miR-199a-5p can promote gastric cancer by inhibition of Klotho protein expression. But little is known regarding to the role of miR-199a-5p/Klotho in regulating NF-κB p65 pathways in the pathogenesis of diabetic kidney disease (DKD). Thus, we explored Klotho and miR-199a-5p in terms of Toll-like receptor-4 (TLR4)/NF-κB p65/neutrophil gelatinase associated lipocalin (NGAL) signaling pathways in high glucose cultured mesangial cells (MCs). We found that high glucose increased miR-199a-5p expression, accompanied by the significantly decreased Klotho expression at both mRNA and protein. High glucose also activated TLR4/NF-κB p65/NGAL signaling pathways and promoted the downstream fibrosis and inflammatory reaction. Additionally, inhibition of miR-199a-5p or exogenous addition of Klotho restrained the activity of TLR4/NF-κB p65/NGAL signaling pathways, which in turn suppressed the inflammation and fibrosis in high glucose cultured MCs. This study provides a new basis to elucidate the protection mechanism of anti-aging protein Klotho in diabetic kidney. For the first time, our study prompts that miR-199a-5p can be used as a new therapeutic targets for DKD.

The Relationship between Serum Osteocalcin Concentration and Glucose and Lipid Metabolism in Patients with Type 2 Diabetes Mellitus ­ The Role of Osteocalcin in Energy Metabolism.

BACKGROUND: Recent animal studies have found that the osteocalcin secreted by osteoblasts could participate in glucose and lipid metabolism. Our study aimed to investigate the relationship between serum osteocalcin concentration and glucose and lipid metabolism in patients with type 2 diabetes mellitus. METHODS: 985 patients with type 2 diabetes were divided into the male group (n = 495) and the postmenopausal female group (n = 490). The average ages were 54.42 ± 10.535 and 64.93 ± 9.277, respectively. We collected the parameters of age, duration, fasting plasma glucose, HbA1c, fasting insulin, fasting C peptide, blood lipid, 25 (OH) VD3, parathyroid hormone (PTH), Alkaline phosphatase (ALP), procollagen type 1 N-terminal propeptide (P1NP), ß-C-terminal telopeptide of type I collagen (ß-CTx), osteocalcin, HOMA-IR, HOMA-ß, body mass index (BMI), and waist-to-hip ratio (WHR). The relationship of osteocalcin and these parameters were analyzed by Pearson/Spearman correlation analysis and stepwise multiple regression analysis. RESULTS: Osteocalcin was negatively correlated with HbA1c (p < 0.05) and it was also an independent relevant factor affecting HbA1c in both groups. Osteocalcin was positively correlated with HOMA-ß and it was an independent relevant factor affecting HOMA-ß in male group (p < 0.01). CONCLUSIONS: These findings indicate the association between serum osteocalcin and glucose metabolism and beta cell function. No relationship was found between osteocalcin and insulin resistance and lipid metabolism in type 2 diabetes.

Suppressor of cytokine signaling (SOCS) 2 attenuates renal lesions in rats with diabetic nephropathy.

Diabetic nephropathy (DN) involves damage to the kidney caused by diabetes. It is characterized by renal hypertrophy, tubular atrophy/dilation and glomerular hyperfiltration. Suppressor of cytokine signaling (SOCS) 2 has recently been indicated to be involved in the pathogenesis of DN, however, the exact regulatory mechanisms remain unclear. This study was conducted to explore the role of SOCS2 in the development and progress of DN in a rat model of streptozocin (STZ)-induced diabetes. Recombinant adenoviruses expressing SOCS2 were used to upregulate the expression of SOCS2 in the kidneys of diabetic rats. Our results demonstrated that intrarenal injection of SOCS2 adenoviruses reduced STZ-induced renal lesions, including renal/glomerular hypertrophy, glomerular hyperfiltration, aberrant inflammation and fibrosis. Increased expression levels of proinflammatory proteins (monocyte chemoattractant protein-1, tumor necrotic factor-alpha and interleukin-6) and profibrotic proteins (transforming growth factor-beta, collagen IV and fibronectin) in the diabetic kidneys were decreased after SOCS2 gene delivery. Additionally, adenovirus-mediated upregulation of renal SOCS2 markedly inhibited STZ-induced phosphorylation increases of Janus kinase (JAK) 2, signal transducer and activator of transcription (STAT) 3, STAT5 and extracellular receptor-activated kinase (ERK) 1/2. In summary, the present research demonstrates that SOCS2 reduces renal lesions associated with diabetes in rats.

Levels of inflammatory cytokines in type 2 diabetes patients with different urinary albumin excretion rates and their correlation with clinical variables.

Although the pathogenetic mechanism of DN has not been elucidated, an inflammatory mechanism has been suggested as a potential contributor. This study was designed to explore the relationship between low-grade inflammation and renal microangiopathy in T2DM. A total of 261 diabetic subjects were divided into three groups according to UAE: a normal albuminuria group, a microalbuminuria group, and a macroalbuminuria group. A control group was also chosen. Levels of hs-CRP, TNF-α, uMCP-1, SAA, SCr, BUN, serum lipid, blood pressure, and HbA1c were measured in all subjects. Compared with the normal controls, levels of hs-CRP, TNF-α, uMCP-1, and SAA in T2DM patients were significantly higher. They were also elevated in the normal albuminuria group, P < 0.05. Compared with the normal albuminuria group, levels of these inflammatory cytokines were significantly higher in the microalbuminuria and macroalbuminuria group, P < 0.01. The macroalbuminuria group also showed higher levels than the microalbuminuria group, P < 0.01. Also they were positively correlated with UAE, SBP, DBP, LDL-C, and TC. We noted no significance correlated with course, TG, or HDL-C. Only TNF-α; was positively correlated with HbA1c. This study revealed the importance of these inflammatory cytokines in DN pathogenesis. Further studies are needed to fully establish the potential of these cytokines as additional biomarkers for the development of DN.

[Effect of mycophenolate on expression of MCP-1 and fibronectin in human mesangial cells induced by high glucose].

AIM: To investigate the effect of high glucose and mycophenolate (MMF) on the expression of MCP-1 in human mesangial cells (HMCs) and fibronectin (FN). METHODS: The HMCs were divided randomly into five groups: control group (5 mmol/L glucose), high glucose group (30 mmol/L glucose), mannitol group (5 mmol/L glucose and 25 mmol/L mannitol), high glucose+MMF-10 group (30 mmol/L glucose plus 10 µg/mL mycophenolate) and high glucose+MMF-100 group (30 mmol/L glucose plus 100 µg/mL mycophenolate). We detected the levels of MCP-1 and fibronectin in each group at 24 h, 48 h and 72 h, respectively. The expression levels of the MCP-1 mRNA were detected by RT-PCR, and the protein expression of MCP-1 and fibronectin was measured by ELISA. RESULTS: Compared with the control group, the levels of the MCP-1 and FN in high glucose group were significantly increased with the expression peak at 48 h (P<0.01). The MMF with different concentration could inhibit the expression of MCP-1 and FN in time- and dose-dependent manner (P<0.05). CONCLUSION: Mycophenolate could inhibit the expressions of MCP-1 and FN in human mesangial cells and it might be expected to delay the development and progression of glomerular sclerosis and interstitial fibrosis.

The changes of platelet-derived growth factor-BB (PDGF-BB) in T2DM and its clinical significance for early diagnosis of diabetic nephropathy.

OBJECTIVE: To investigate urinary excretion of platelet-derived growth factor-BB (PDGF-BB) during the different stages of diabetic nephropathy (DN) in type 2 diabetes mellitus (T2DM) as well as its clinical significance. METHODS: Sixty-five cases with T2DM were divided into three groups: normoalbuminuric group [N-UAlb; urine albumin excretion (UAE) <30 mg/24 h, n=25], microalbuminuric group [M-UAlb; UAE 30-300 mg/24 h, n=20], and macroalbuminuric group [L-UAlb; UAE >300 mg/ 24 h, n=20]. The urinary excretion rates of PDGF-BB were determined by a quantitative sandwich enzyme-linked immunosorbent assay (ELISA) in all the cases and 27 subjects of control. RESULTS: The excretion rates of PDGF-BB in T2DM groups were markedly higher than that in control (P<0.001). Moreover, the excretion rates of PDGF-BB increased with the increase of UAE and there were significant differences among the three groups (P<0.05) except the groups of M-UAlb and L-UAlb. Urinary PDGF-BB was also positively correlated with UAE, triglyceride (TG), cholesterol (CHO), low-density lipoprotein (LDL) and negatively correlated with creatinine clearance (Ccr), high-density lipoprotein (HDL), while had no significance correlated with glycohemoglobin A1c (HbA1c). CONCLUSION: PDGF-BB might play a very important role in the initiation and progression of DN. Measurements of urine PDGF-BB in T2DM could be used for early diagnosis of diabetic renal dysfunction.

Prebiotic oligosaccharides change the concentrations of short-chain fatty acids and the microbial population of mouse bowel.

The purpose of this study was to clarify effects of selected oligosaccharides on concentrations of cecal short-chain fatty acids (SCFAs), total large bowel wet weight and wall weight, and cecal microbiota levels in mice. Mice were respectively given gavage of selected fructooligosaccharides (FOS), galactooligosaccharides (GOS), mannanoligosaccharides (MOS), and chitooligosaccharides (COS) [1000 mg/(kg body weight.d)]. Control group was given physiological saline solution. After 14 d treatment, SCFAs and lactate in mice cecum were significantly increased (P<0.05) by intake of oligosaccharides, especially FOS and GOS. Thus, providing these oligosaccharides as ingredients in nutritional formulas may benefit the gastrointestinal tract.

Clinical significance and different levels of urinary monocyte chemoattractant protein-1 in type 2 diabetes mellitus.

OBJECTIVE: Monocyte chemoattractant protein-1(MCP-1) is a cytokine that exhibits most potent chemotactic activity toward monocytes. It is suggested to be implicated in the development and progression of diabetic nephropathy by playing a role in infiltration of monocyte/macrophage. Recent studies have demonstrated that urinary monocyte chemoattractant protein-1 (uMCP-1) is different at different stages of diabetic nephropathy. Based on these findings, the aim of this study is to examine the level of uMCP-1 and its clinical significance at different stages of diabetic nephropathy and at the same time to describe the relationship between uMCP-1 and the various parameters. METHODS: Fifty-nine cases with type 2 diabetes mellitus (T2DM) were divided into three groups according to urine albumin excretion (UAE): normal albuminuria group, microalbuminuria group and macroalbuminuria group. The levels of uMCP-1, protein excretion, blood urea nitrogen (BUN), serum creatinine (s-Cr), glycohemoglobin A1c (HbA1c), blood pressure and blood fat were measured in 59 patients with T2DM and 27 healthy adults as controls. Results Compared with normal control, levels of uMCP-1 in T2DM were significantly high, which were already elevated in normal albuminuria group. Compared with normal albuminuria group, levels of uMCP-1 in microalbuminuria group and macroalbuminuria group were significantly high. Levels of uMCP-1 in macroalbuminuria group were higher than those in microalbuminuria group. The level of uMCP-1 was positively correlated with UAE, systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) in T2DM patients, while it had no significant correlation with HbA1c(,) triglyceride (TG) and high density lipoprotein cholesterol (HDL-C). CONCLUSIONS: MCP-1 is suggested to be implicated in the development and progression of diabetic nephropathy. It is very important to measure the level of uMCP-1 in the diagnosis and intervention of early diabetic nephropathy.