Effects of Glutathione Tablets on Ferroptosis Pathway and Oxidative Stress-Related Indexes in Serum of Patients Undergoing Sevoflurane Inhalation General Anesthesia and Its Clinical Significance.

Objective: To explore the effect of glutathione on serum oxidative stress, inflammatory reaction, and brain injury in patients with Sevoflurane inhalation general anesthesia based on iron metabolism pathway. Methods: From January 2018 to January 2023, 120 patients undergoing Sevoflurane inhalation anesthesia in Xingtai Third Hospital were divided into a control group and an observation group. The control group was given routine treatment, and the observation group patients were given oral glutathione tablets 2 weeks before anesthesia based on the control group. Relevant basic data of patients were collected 3 days before operation (T0), 1 day after the operation (T1), 3 days (T2), and 7 days (T3) respectively, and the serum oxidative stress indicators of patients in each group were measured by ELISA: SOD, MDA, GSH, Hif-1α, ferroptosis related indicators: SIRT3, GPX4; related inflammatory indicators: IL-1ß, TGF-ß, IL-33; neuronal injury related proteins: MBP, NGF, and statistical analysis of the data. Results: There was no significant difference in general conditions and operation time between the two groups (P > .05). Compared with the control group, the observation group showed significant differences in oxidative stress indicators: SOD in the observation group at T1, SOD, and Hif-1α in the observation group at T2, and SOD, MDA, GSH and Hif-1α in the observation group at T3. 1α, there were significant differences compared with the indicators of the control group at the same time (P < .001). In terms of inflammatory factor indicators, compared with the control group, there were significant differences in IL-1ß at T1, TGF-ß, and IL-33 at T2, and IL-1ß, TGF-ß and IL-33 at T3. (P < .001). In terms of ferroptosis indicators, compared with the control group, there were significant differences in SIRT3 at T1, SIRT3, and GPX4 at T2, and SIRT3 and GPX4 at T3 (P < .001). In terms of nerve injury-related proteins, in patients, MBP levels were negatively correlated with SIRT3 (r=-0.8979, P < .0001), MBP levels were positively correlated with GPX4 (r=0.528, P < .0001), and NGF levels were positively correlated with SIRT3 (r=0.8979, P < .0001), NGF level was negatively correlated with GPX4 (r=0.528, P < .0001). Conclusion: Glutathione tablets can alleviate sevoflurane-induced ferroptosis and oxidative stress by elevating GPX4 protein levels, and glutathione tablets have an ameliorative effect on brain injury in patients with sevoflurane inhalation anesthesia.

CCX559 is a potent, orally-administered small molecule PD-L1 inhibitor that induces anti-tumor immunity.

The interaction of PD-L1 with PD-1 is a major immune checkpoint that limits effector T cell function against cancer cells; monoclonal antibodies that block this pathway have been approved in multiple tumor indications. As a next generation therapy, small molecule inhibitors of PD-L1 have inherent drug properties that may be advantageous for certain patient populations compared to antibody therapies. In this report we present the pharmacology of the orally-available, small molecule PD-L1 inhibitor CCX559 for cancer immunotherapy. CCX559 potently and selectively inhibited PD-L1 binding to PD-1 and CD80 in vitro, and increased activation of primary human T cells in a T cell receptor-dependent fashion. Oral administration of CCX559 demonstrated anti-tumor activity similar to an anti-human PD-L1 antibody in two murine tumor models. Treatment of cells with CCX559 induced PD-L1 dimer formation and internalization, which prevented interaction with PD-1. Cell surface PD-L1 expression recovered in MC38 tumors upon CCX559 clearance post dosing. In a cynomolgus monkey pharmacodynamic study, CCX559 increased plasma levels of soluble PD-L1. These results support the clinical development of CCX559 for solid tumors; CCX559 is currently in a Phase 1, first in patient, multicenter, open-label, dose-escalation study (ACTRN12621001342808).

Protective effects of Lycium barbarum polysaccharide on ovariectomy­induced cognition reduction in aging mice.

Women experience cognitive decline as they age due to the decrease in estrogen levels following menopause. Currently, effective pharmaceutical treatments for age­related cognitive decline are lacking; however, several Traditional Chinese medicines have shown promising effects. Lycium barbarum polysaccharides (LBPs) were found to exert a wide variety of biological activities, including anti­inflammatory, antioxidant and anti­aging effects. However, to the best of our knowledge, the neuroprotective actions of LBP on cognitive impairment induced by decreased levels of estrogen have not yet been determined. To evaluate the effects of LBP on learning and memory impairment in an animal model of menopause, 45 female ICR mice were randomly divided into the following three groups: i) Sham; ii) ovariectomy (OVX); and iii) OVX + LBP treatment. The results of open­field and novel object recognition tests revealed that mice in the OVX group had learning and memory impairments, and lacked the ability to recognize and remember new objects. Notably, these deficits were attenuated following LBP treatment. Immunohistochemical staining confirmed the protective effects of LBP on hippocampal neurons following OVX. To further investigate the underlying mechanism of OVX in mice, mRNA sequencing of the hippocampal tissue was performed, which revealed that the Toll­like receptor 4 (TLR4) inflammatory signaling pathway was significantly upregulated in the OVX group. Moreover, reverse transcription­quantitative PCR and immunohistochemical staining demonstrated that OVX induced hippocampal injury, upregulated the expression levels of TLR4, myeloid differentiation factor 88 and NF­κB, and increased the expression of TNF­α, IL­6 and IL­1ß inflammatory factors. Conversely, LBP treatment downregulated the expression levels of mRNAs and proteins associated with the TLR4/NF­κB signaling pathway, decreased the inflammatory response and reduced neuronal injury in mice that underwent OVX. In conclusion, the findings of the present study indicated that oral LBP treatment may alleviate OVX­induced cognitive impairments by downregulating the expression levels of mRNAs and proteins associated with the TLR4/NF­κB signaling pathway, thereby reducing neuroinflammation and damage to the hippocampal neurons. Thus, LBP may represent a potential agent for the prevention of learning and memory impairments in patients with accelerated aging caused by estrogen deficiency.

HSP60 participates in the anti-glioma effects of curcumin.

The chaperone protein heat shock protein 60 (HSP60) is considered a tumor promoter in several types of primary human tumors, where it orchestrates a broad range of survival programs. Curcumin (CCM) is well-established to exhibit several anticancer properties with an excellent safety profile. Our previous study showed that CCM suppresses extracellular HSP60 expression, which is typically released by activated microglia, and acts as an inflammatory factor by binding to Toll-like receptor 4 (TLR-4) on the cell membrane. The present study assessed whether CCM exerted its anti-neuroglioma effects on U87 cells via inhibition of HSP60/TLR-4 signaling, similar to that in microglia. The results demonstrated that CCM significantly inhibited the viability and invasive capacity of neuroglioma U87 cells as evidenced by a Cell Counting Kit-8 assay. Western blotting and ELISA results showed that CCM decreased the expression of HSP60 and its transcriptional factor, heat shock factor 1, and reduced HSP60 release. Accordingly, TLR-4, as the target of HSP60, and its downstream signaling proteins myeloid differentiation primary response 88 (MYD88), NF-κB, inducible nitric oxide synthase and cytokines IL-1ß and IL-6 were downregulated by CCM. The expression levels of apoptotic factors associated with NF-κB activation, including TNF-α and caspase-3 were increased in U87 cells by CCM treatment, while p53 expression, a tumor suppressor, was shown to be decreased. Based on the results of the present study, CCM may exert its anti-tumor effects in U87 cells by inhibiting the HSP60/TLR-4/MYD88/NF-κB pathway and inducing tumor cell apoptosis. Thus, CCM may be used as a potential therapy for the clinical treatment of neuroglioma.

CCR2 antagonism leads to marked reduction in proteinuria and glomerular injury in murine models of focal segmental glomerulosclerosis (FSGS).

Focal segmental glomerulosclerosis (FSGS) comprises a group of uncommon disorders that present with marked proteinuria, nephrotic syndrome, progressive renal failure and characteristic glomerular lesions on histopathology. The current standard of care for patients with FSGS include immunosuppressive drugs such as glucocorticoids followed by calcineurin inhibitors, if needed for intolerance or inadequate response to glucocorticoids. Renin-angiotensin-aldosterone (RAAS) blockers are also used to control proteinuria, an important signature of FSGS. Existing treatments, however, achieved only limited success. Despite best care, treatment failure is common and FSGS is causal in a significant proportion of end stage renal disease. Thus, an unmet need exists for novel disease modifying treatments for FSGS. We employed two widely-used murine models of FSGS to test the hypothesis that systemic inhibition of chemokine receptor CCR2 would have therapeutic benefit. Here we report that administration CCX872, a potent and selective small molecule antagonist of CCR2, achieved rapid and sustained attenuation of renal damage as determined by urine albumin excretion and improved histopathological outcome. Therapeutic benefit was present when CCX872 was used as a single therapy, and moreover, the combination of CCX872 and RAAS blockade was statistically more effective than RAAS blockade alone. In addition, the combination of CCR2 and RAAS blockade was equally as effective as endothelin receptor inhibition. We conclude that specific inhibition of CCR2 is effective in the Adriamycin-induced and 5/6 nephrectomy murine models of FSGS, and thus holds promise as a mechanistically distinct therapeutic addition to the treatment of human FSGS.

CC chemokine receptor 2 promotes recruitment of myeloid cells associated with insulin resistance in nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is a common disease, closely associated with obesity and insulin resistance. We investigated the presence of a subset of myeloid cells associated with metabolic disturbance in the liver of patients with NAFLD and a murine model of obesity-induced liver disease. Gene and protein expression in liver and serum was investigated with RT-PCR or ELISA and correlated to clinical disease. Liver-infiltrating immune cells were isolated from normal or diseased human liver for flow cytometric analysis. In animal experiments, mice were fed a high-fat diet (60% of calories from fat) for 16 wk, or high-fat diet with 30% fructose for 32 wk to induce steatohepatitis and fibrosis. A small molecule inhibitor of CC chemokine receptor 2 (CCR2), CCX872, was administered to some mice. A subset of CD11c+CD206+ immune cells was enriched in human liver tissue, and greater infiltration was observed in NAFLD. The presence of CD11c+CD206+ myeloid cells correlated with systemic insulin resistance. CD11c+CD206+ cells expressed high levels of CCR2, and liver CC chemokine ligand 2 (CCL2) expression was increased in nonalcoholic steatohepatitis and correlated with disease activity. In mice, CCR2 inhibition reduced infiltration of liver CD11b+CD11c+F4/80+ monocytes, which are functional homologs of human CD11c+CD206+ cells, and improved liver injury and glycemic control. A role for CCR2/CCL2 in human NAFLD has long been postulated. These data confirm a role for this chemokine/receptor axis, through mediating adipose and hepatic infiltration of myeloid cells. Inhibition of CCR2 improved hepatic inflammation and fibrosis in murine models of NAFLD. These data confirm the rationale for targeting CCR2 to treat NAFLD. NEW & NOTEWORTHY These data show for the first time that CD11c+CD206+ myeloid cells, previously associated with human adipose tissue inflammation, infiltrate into liver tissue in nonalcoholic fatty liver disease. These cells express CCR2. Inhibition of CCR2 in mice inhibits hepatic inflammation caused by a murine homolog of these myeloid cells and improves experimental liver disease.

IL-17-Secreting γδ T Cells Are Completely Dependent upon CCR6 for Homing to Inflamed Skin.

mAbs that neutralize IL-17 or its receptor have proven efficacious in treating moderate-to-severe psoriasis, confirming IL-17 as an important driver of this disease. In mice, a rare population of T cells, γδT17 cells, appears to be a dominant source of IL-17 in experimental psoriasis. These cells traffic between lymph nodes and the skin, and are identified by their coexpression of the TCR variable regions γ4 and δ4. These cells are homologous to the Vγ9Vδ2 T cell population identified in human psoriatic plaques. In this study we report that a potent and specific small molecule antagonist of the CCR6 chemokine receptor, CCX2553, was efficacious in reducing multiple aspects of psoriasis in two different murine models of the disease. Administration of CCX2553 ameliorated skin inflammation in both the IL-23-induced ear swelling model and the topical imiquimod model, and significantly reduced the number of γδT17 cells in inflamed skin. γδT17 cells were greatly reduced in imiquimod-treated skin of CCR6-/- mice, but adoptively transferred wild-type (CCR6+/+) γδT17 cells homed normally to the skin of imiquimod-treated CCR6-/- mice. Our data suggest that γδT17 cells are completely dependent on CCR6 for homing to psoriasiform skin. Thus, CCR6 may constitute a novel target for a mechanistically distinct therapeutic approach to treating psoriasis.

Neuroprotective effect of heat shock protein 60 on matrine-suppressed microglial activation.

Matrine (MT) is the primary active alkaloid separated from members of the Sophora genus. Previous studies have reported that MT has anti-inflammatory effects in the central nervous system (CNS). However, the underlying molecular mechanism of the neuroprotective effect of MT remains unclear, particularly the role of heat shock protein 60 (HSP60). Microglia are macrophages in the CNS that serve an essential role in the innate immune system by producing various proinflammatory and neurotoxic factors. In addition, HSP60 is released by activated microglia causing an autoimmune response. The present study aimed to investigate whether MT could inhibit the activation of microglia via suppressing the HSP60 signaling pathway. The results demonstrated that the expression and release of HSP60 in LPS-activated BV2 microglial cells was significantly decreased by MT treatment. Extracellular HSP60 is a ligand of toll like receptor 4 (TLR-4); thus, it was hypothesized that secreted HSP60 could bind to TLR-4 on microglia and activate the TLR-4 signaling pathway. As expected, western blotting and ELISA results revealed that MT significantly inhibited the LPS-induced increase in TLR-4, myeloid differentiation primary response protein MyD88, caspase-3 and tumor necrosis factor-α. In conclusion, the results of the present study provide a novel direction for the prevention and treatment of neurodegenerative diseases characterized by microglial activation.

Tamaractam, a New Bioactive Lactam from Tamarix ramosissima, Induces Apoptosis in Rheumatoid Arthritis Fibroblast-Like Synoviocytes.

Chemical investigation of Tamarix ramosissima Ledeb, a traditional herbal medicine used for rheumatoid arthritis (RA) treatment in northwest China, led to the discovery of a new phenolic aromatic rings substituted lactam, tamaractam (1), together with the previously reported compounds cis-N-feruloyl-3-O-methyldopamine (2) and trans-N-feruloyl-3-O-methyldopamine (3). The structures of the compounds were determined by high resolution electrospray ionization mass spectroscopy (HRESIMS) and 1D and 2D-NMR experiments, as well as comparison with the literature data. The effects of the three compounds on the viability of RA fibroblast-like synoviocytes (RA-FLS) were assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Pro-apoptosis effect of compound 1 in RA-FLS was further investigated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay, activated caspase-3/7 level assessment using luminescence assay, and sub-G1 fraction measurement using flow cytometry. It was found that these three compounds displayed variable proliferation inhibitory activity in RA-FLS, and compound 1 exhibited the strongest effect. Compound 1 could remarkably induce cellular apoptosis of RA-FLS, increase activated caspase-3/7 levels, and significantly increase sub-G1 fraction in the cell cycle. The results suggested that compound 1 may inhibit the proliferation of RA-FLS through apoptosis-inducing effect, and these compounds may contribute to the anti-RA effect of T. ramosissima.

Early pancreatic cancer lesions suppress pain through CXCL12-mediated chemoattraction of Schwann cells.

Pancreatic ductal adenocarcinoma (PDAC) cells (PCC) have an exceptional propensity to metastasize early into intratumoral, chemokine-secreting nerves. However, we hypothesized the opposite process, that precancerous pancreatic cells secrete chemokines that chemoattract Schwann cells (SC) of nerves and thus induce ready-to-use routes of dissemination in early carcinogenesis. Here we show a peculiar role for the chemokine CXCL12 secreted in early PDAC and for its receptors CXCR4/CXCR7 on SC in the initiation of neural invasion in the cancer precursor stage and the resulting delay in the onset of PDAC-associated pain. SC exhibited cancer- or hypoxia-induced CXCR4/CXCR7 expression in vivo and in vitro and migrated toward CXCL12-expressing PCC. Glia-specific depletion of CXCR4/CXCR7 in mice abrogated the chemoattraction of SC to PCC. PDAC mice with pancreas-specific CXCL12 depletion exhibited diminished SC chemoattraction to pancreatic intraepithelial neoplasia and increased abdominal hypersensitivity caused by augmented spinal astroglial and microglial activity. In PDAC patients, reduced CXCR4/CXCR7 expression in nerves correlated with increased pain. Mechanistically, upon CXCL12 exposure, SC down-regulated the expression of several pain-associated targets. Therefore, PDAC-derived CXCL12 seems to induce tumor infiltration by SC during early carcinogenesis and to attenuate pain, possibly resulting in delayed diagnosis in PDAC.

Resveratrol inhibits oligomeric Aß-induced microglial activation via NADPH oxidase.

Microglia­mediated neuroinflammation is key in the pathogenesis of Alzheimer's disease (AD). Several studies have suggested that NADPH oxidase contributes to microglia­mediated neuroinflammation. Resveratrol, which is a natural polyphenolic compound, exerts neuroprotective effects in AD due to its anti­inflammatory properties. The present study aimed to investigate the effects of resveratrol on the activation of oligomeric amyloid ß (oAß)­induced BV­2 microglia, and to determine the role of NADPH oxidase in these effects. Microglial proliferation was measured by high­content screening cell counting and using a bromodeoxyuridine incorporation assay. In addition, the levels of reactive oxygen species (ROS), nitric oxide (NO), tumor necrosis factor (TNF)­α and interleukin (IL)­1ß were assessed. The results of the present study demonstrated that resveratrol inhibited the proliferation of oAß­induced microglia and the production of pro­inflammatory factors, including ROS, NO, TNF­α and IL­1ß. Subsequent mechanistic investigations demonstrated that resveratrol inhibited the oAß­induced mRNA and protein expression levels of p47phox and gp91phox. These results suggested that NADPH oxidase may be a potential target for AD treatment, and resveratrol may be a valuable natural product possessing therapeutic potential against AD.

Trichodimerol and sorbicillin induced apoptosis of HL-60 cells is mediated by reactive oxygen species.

In this study, two secondary metabolite compounds, trichodimerol and sorbicillin were isolated from the mycelial mass of the marine fungus Trichothecium sp.. It was found that trichodimerol and sorbicillin exhibited strong cytotoxic activity with IC50 values from 6.55 µM to 28.55 µM on three cancer cell lines, HL-60, U937 and T47D. Then HL-60 cells were employed for apoptotic assay. The two compounds could significantly increase the levels of activated caspase-3/7 in a dose-dependent manner and remarkably increase sub-G1 fraction in the cell cycle using flow cytometry, indicating that trichodimerol and sorbicillin potently induced apoptosis in HL-60 cells. Trichodimerol or sorbicillin induced ROS levels also showed dose-dependent increases in HL-60 cells as measured by 2',7'-Dichlorodihydrofluorescein diacetate (DCFH-DA), while trichodimerol or sorbicillin induced apoptosis was effectively blocked by the ROS inhibitor N-acetyl-L-cysteine (NAC). Western blot results showed that trichodimerol or sorbicillin could increase phosphorylated p38 levels and decrease ERK and phosphorylated ERK levels in a concentration-dependent manner. Our findings suggest that the pro-apoptosis effects of trichodimerol and sorbicillin were mediated by ROS, while activation of p38 and inhibition of ERK may be involved in these effects.

HSP60 is involved in the neuroprotective effects of naloxone.

Heat shock protein (HSP)60 is primarily a mitochondrial protein. Previous experiments have found that changes in the location of intracellular HSP60 have been associated with apoptosis. Extracellular HSP60 mediates apoptosis via its ligand, Toll­like receptor (TLR)-4. TLR-4 is an important factor expressed on microglia, with a central role in generating neuroimmune responses in the pathogenesis of neurodegenerative disorders. Naloxone is a highly effective nonselective opioid receptor antagonist, and has been reported to be pharmacologically beneficial for the treatment of brain diseases through inhibiting microglia activation. However, the mechanisms underlying these beneficial effects of naloxone remain poorly understood. The present study aimed to investigate the role of HSP60 in the neuroprotective effects of naloxone on the production of proinflammatory mediators in lipopolysaccharide (LPS)-stimulated BV2 murine microglial cells and the possible signaling pathways involved. The results demonstrated that naloxone significantly inhibited the expression and release of HSP60 in BV2 cells. The expression levels of heat shock factor (HSF)-1 were upregulated in LPS­activated BV2 cells, which indicated that the increased expression of HSP60 was driven by HSF-1 activation. However, increased HSF­1 levels may be downregulated by naloxone. The levels of TLR­4 were elevated in activated BV2 cells, and then inhibited by naloxone. Activation of TLR­4 is characterized by activation of nuclear factor-κB (NF-κB) followed by the production of various proinflammatory and neurotoxic factors. Data from the present study demonstrated that naloxone reduced the expression levels of NF-κB and its upstream protein caspase­3, and reduced the LPS-induced production of nitric oxide, inducible nitric oxide synthase, tumor necrosis factor α, interleukin-1ß and interleukin-6 in BV2 microglia. In light of this data, it was concluded that naloxone may exert its neuroprotective and anti­inflammatory effects by inhibiting microglia activation through a HSP60­TLR­4­NF­κB signaling pathway.

C-X-C motif chemokine 12/C-X-C chemokine receptor type 7 signaling regulates breast cancer growth and metastasis by modulating the tumor microenvironment.

INTRODUCTION: Although C-X-C motif chemokine 12 (CXCL12) has been shown to bind to C-X-C chemokine receptor type 7 (CXCR7), the exact molecular mechanism regulations by CXCL12/CXCR7 axis in breast tumor growth and metastasis are not well understood. CXCR7 expression has been shown to be upregulated during pathological processes such as inflammation and cancer. METHODS: Breast cancer cell lines were genetically silenced or pharmacologically inhibited for CXCR7 and/or its downstream target signal transducer and activator of transcription 3 (STAT3). 4T1 or 4T1 downregulated for CXCR7 and 4T1.2 breast cancer cell lines were injected in mammary gland of BALB/c mice to form tumors, and the molecular pathways regulating tumor growth and metastasis were assessed. RESULTS: In this study, we observed that CXCL12 enhances CXCR7-mediated breast cancer migration. Furthermore, genetic silencing or pharmacologic inhibition of CXCR7 reduced breast tumor growth and metastasis. Further elucidation of mechanisms revealed that CXCR7 mediates tumor growth and metastasis by activating proinflammatory STAT3 signaling and angiogenic markers. Furthermore, enhanced breast tumorigenicity and invasiveness were associated with macrophage infiltration. CXCR7 recruits tumor-promoting macrophages (M2) to the tumor site through regulation of the macrophage colony-stimulating factor (M-CSF)/macrophage colony-stimulating factor receptor (MCSF-R) signaling pathway. In addition, CXCR7 regulated breast cancer metastasis by enhancing expression of metalloproteinases (MMP-9, MMP-2) and vascular cell-adhesion molecule-1 (VCAM-1). We also observed that CXCR7 is highly expressed in invasive ductal carcinoma (IDC) and metastatic breast tissue in human patient samples. In addition, high CXCR7 expression in tumors correlates with worse prognosis for both overall survival and lung metastasis-free survival in IDC patients. CONCLUSION: These observations reveal that CXCR7 enhances breast cancer growth and metastasis via a novel pathway by modulating the tumor microenvironment. These findings identify CXCR7-mediated STAT3 activation and modulation of the tumor microenvironment as novel regulation of breast cancer growth and metastasis. These studies indicate that new strategies using CXCR7 inhibitors could be developed for antimetastatic therapy.

Scavenging of blood glutamate for enhancing brain-to-blood glutamate efflux.

The presence of excess glutamate in the brain interstitial fluid characterizes several acute pathological conditions of the brain, including traumatic brain injury and stroke. It has been demonstrated that it is possible to eliminate excess glutamate in the brain by decreasing blood glutamate levels and, accordingly, accelerating the brain-to-blood glutamate efflux. It is feasible to accomplish this process by activating blood resident enzymes in the presence of the respective glutamate cosubstrates. In the present study, several glutamate cosubstrates and cofactors were studied in an attempt to identify the optimal conditions to reduce blood glutamate levels. The administration of a mixture of 1 mM pyruvate and oxaloacetate (Pyr/Oxa) for 1 h decreased blood glutamate levels by ≤50%. The addition of lipoamide to this mixture resulted in a further reduction in blood glutamate levels of >80%. In addition, in vivo experiments showed that lipoamide together with Pyr/Oxa is able to decrease blood glutamate levels to a greater extent than Pyr/Oxa alone, and accordingly, this enhances the glutamate efflux from the brain to the blood. These results may outline a novel neuroprotective strategy with increased effectiveness for the removal of excess brain glutamate in various neurodegenerative conditions.

Experimental evidence for the use of CCR2 antagonists in the treatment of type 2 diabetes.

OBJECTIVE: CCR2 inhibition has produced promising experimental and clinical anti-hyperglycemic effects. These results support the thesis that insulin resistance and Type 2 diabetes (T2D) are associated with chronic unresolved inflammation. The aim of this study was to provide a broad analysis of the various physiological changes occurring in mouse models of T2D in connection with pharmacological CCR2 inhibition. MATERIALS/METHODS: A mouse-active chemical analogue of the clinical candidate CCX140-B was tested in diet-induced obese (DIO) mice and db/db mice. Measurements included: adipose tissue inflammatory macrophage counts; peripheral blood glucose levels at steady-state and after glucose and insulin challenges; peripheral blood insulin and adiponectin levels; 24-h urine output and urinary glucose levels; pancreatic islet number and size; hepatic triglyceride and glycogen content; and hepatic glucose-6-phosphatase levels. RESULTS: In DIO mice, the CCR2 antagonist completely blocked the recruitment of inflammatory macrophages to visceral adipose tissue. The mice exhibited reduced hyperglycemia and insulinemia, improved insulin sensitivity, increased circulating adiponectin levels, decreased pancreatic islet size and increased islet number. It also reduced urine output, glucose excretion, hepatic glycogen and triglyceride content and glucose 6-phosphatase levels. Similar effects were observed in the db/db diabetic mice. CONCLUSIONS: These data indicate that pharmacological inhibition of CCR2 in models of T2D can reduce inflammation in adipose tissue, alter hepatic metabolism and ameliorate multiple diabetic parameters. These mechanisms may contribute to the promising anti-diabetic effects seen in humans with at least one CCR2 antagonist.

CCR2 antagonist CCX140-B provides renal and glycemic benefits in diabetic transgenic human CCR2 knockin mice.

Chemokine (C-C motif) receptor 2 (CCR2) is central for the migration of monocytes into inflamed tissues. The novel CCR2 antagonist CCX140-B, which is currently in two separate phase 2 clinical trials in diabetic nephropathy, has recently been shown to reduce hemoglobin A1c and fasting blood glucose levels in type 2 diabetics. In this report, we describe the effects of this compound on glycemic and renal function parameters in diabetic mice. Since CCX140-B has a low affinity for mouse CCR2, transgenic human CCR2 knockin mice were generated and rendered diabetic with either a high-fat diet (diet-induced obesity) or by deletion of the leptin receptor gene (db/db). CCX140-B treatment in both models resulted in decreased albuminuria, which was associated with decreased glomerular hypertrophy and increased podocyte density. Moreover, treatment of diet-induced obese mice with CCX140-B resulted in decreased levels of fasting blood glucose and insulin, normalization of homeostatic model assessment of insulin resistance values, and decreased numbers of adipose tissue inflammatory macrophages. Unlike other CCR2 antagonists, CCX140-B had no effect on plasma levels of the CCR2 ligand CCL2 or on the numbers of blood monocytes. These results support the ongoing evaluation of this molecule in diabetic subjects with impaired renal function.

Characterization of CCX140-B, an orally bioavailable antagonist of the CCR2 chemokine receptor, for the treatment of type 2 diabetes and associated complications.

The following manuscript was published as a Fast Forward article on February 29, 2012: Sullivan TJ, Dairaghi DJ, Krasinski A, Miao Z, Wang Y, Zhao BN, Baumgart T, Berahovich R, Ertl LS, Pennell A, Seitz L, Miao S, Ungashe S, Wei Z, Johnson D, Boring L, Tsou C-L, Charo IF, Bekker P, Schall TJ, and Jaen JC, Characterization of CCX140-B, an orally bioavailable antagonist of the CCR2 chemokine receptor, for the treatment of type 2 diabetes and associated complications. J Pharmacol Exp Ther jpet.111.190918; doi:10.1124/jpet.111.190918 It was later found that the chemical identity of a compound cited in the article, CCX140-B, was not sufficiently disclosed. The authors are unable, at this time, to provide the chemical identity of CCX140-B in accordance with the editorial policies of The Journal of Pharmacology and Experimental Therapeutics. As a result, the authors have voluntarily withdrawn this manuscript from publication. We apologize for any inconvenience this may cause JPET's readers.

CXCR7 protein is not expressed on human or mouse leukocytes.

Since the discovery that CXCR7 binds to CXCL12/SDF-1α, the role of CXCR7 in CXCL12-mediated biological processes has been under intensive scrutiny. However, there is no consensus in the literature on the expression of CXCR7 protein by peripheral blood cells. In this study we analyzed human and mouse leukocytes and erythrocytes for CXCR7 protein expression, using a competitive CXCL12 binding assay as well as by flow cytometry and immunohistochemistry using multiple CXCR7 Abs. CXCR7(-/-) mice were used as negative controls. Together, these methods indicate that CXCR7 protein is not expressed by human peripheral blood T cells, B cells, NK cells, or monocytes, or by mouse peripheral blood leukocytes. CXCR7 protein is, however, expressed on mouse primitive erythroid cells, which supply oxygen to the embryo during early stages of development. These studies therefore suggest that, whereas CXCR7 protein is expressed by primitive RBCs during murine embryonic development, in adult mammals CXCR7 protein is not expressed by normal peripheral blood cells.