Homodimeric Granzyme A Opsonizes Mycobacterium tuberculosis and Inhibits Its Intracellular Growth in Human Monocytes via Toll-Like Receptor 4 and CD14.

Mycobacterium tuberculosis (Mtb)-specific γ9δ2 T cells secrete granzyme A (GzmA) protective against intracellular Mtb growth. However, GzmA-enzymatic activity is unnecessary for pathogen inhibition, and the mechanisms of GzmA-mediated protection remain unknown. We show that GzmA homodimerization is essential for opsonization of mycobacteria, altered uptake into human monocytes, and subsequent pathogen clearance within the phagolysosome.

The actions of C-peptide in HEK293 cells are dependent upon insulin and extracellular glucose concentrations.

Connecting peptide, or C-peptide, is a part of the insulin prohormone and is essential for the proper folding and processing of the mature insulin peptide. C-peptide is released from the same beta cell secretory granules as insulin in equimolar amounts. However, due to their relative stabilities in plasma, the two peptides are detected in the circulation at ratios of approximately 4:1 to 6:1 (C-peptide to insulin), depending on metabolic state.

Neutrophil Myeloperoxidase Derived Chlorolipid Production During Bacteria Exposure.

Neutrophils are the most abundant white blood cells recruited to the sites of infection and inflammation. During neutrophil activation, myeloperoxidase (MPO) is released and converts hydrogen peroxide to hypochlorous acid (HOCl). HOCl reacts with plasmalogen phospholipids to liberate 2-chlorofatty aldehyde (2-ClFALD), which is metabolized to 2-chlorofatty acid (2-ClFA).

The Deductive Reasoning Strategy Enables Biomedical Breakthroughs.

G protein-coupled receptors (GPCRs) transmit the signals of a variety of hormones and neurotransmitters and are targets of more than 30% of all FDA-approved drugs. We developed an approach for identifying the endogenous ligands for a family of orphan GPCRs that enables the development of novel therapeutics for the potential treatment of a wide variety of disorders including pain, diabetes, appetitive behaviors, infertility and obesity. With this approach, we have deorphanized five previously orphaned GPCRs.

Signaling in rat brainstem via Gpr160 is required for the anorexigenic and antidipsogenic actions of cocaine- and amphetamine-regulated transcript peptide.

Recent work identified Gpr160 as a candidate receptor for cocaine- and amphetamine-regulated transcript peptide (CARTp) and described its role in pain modulation. The aims of the present study were to determine if Gpr160 is required for the CARTp's ability to reduce food intake and water intake and to initially identify the distribution of Gpr160-like immunoreactivity (Gpr160ir) in the rat brain. A passive immunoneutralization approach targeting Gpr160 was used to block the behavioral effects of a pharmacological dose of CARTp in the fourth cerebroventricle (4V) of rats and to determine the importance of endogenously produced CARTp in the control of ingestive behaviors.

GPR183-Oxysterol Axis in Spinal Cord Contributes to Neuropathic Pain.

Neuropathic pain is a debilitating public health concern for which novel non-narcotic therapeutic targets are desperately needed. Using unbiased transcriptomic screening of the dorsal horn spinal cord after nerve injury we have identified that (Epstein-Barr virus-induced gene 2) is upregulated after chronic constriction injury (CCI) in rats. GPR183 is a chemotactic receptor known for its role in the maturation of B cells, and the endogenous ligand is the oxysterol 7,25-dihydroxycholesterol (7,25-OHC).

GPR160 de-orphanization reveals critical roles in neuropathic pain in rodents.

Treating neuropathic pain is challenging and novel non-opioid-based medicines are needed. Using unbiased receptomics, transcriptomic analyses, immunofluorescence, and in situ hybridization, we found that the expression of the orphan GPCR Gpr160 and GPR160 increased in the rodent dorsal horn of the spinal cord following traumatic nerve injury. Genetic and immunopharmacological approaches demonstrated that GPR160 inhibition in the spinal cord prevented and reversed neuropathic pain in male and female rodents without altering normal pain response.

TREX1 is expressed by microglia in normal human brain and increases in regions affected by ischemia.

Background: Mutations in the three-prime repair exonuclease 1 (TREX1) gene have been associated with neurological diseases, including Retinal Vasculopathy with Cerebral Leukoencephalopathy (RVCL). However, the endogenous expression of TREX1 in human brain has not been studied.

Methods: We produced a rabbit polyclonal antibody (pAb) to TREX1 to characterize TREX1 by Western blotting (WB) of cell lysates from normal controls and subjects carrying an RVCL frame-shift mutation.

2-Chlorofatty acids: lipid mediators of neutrophil extracellular trap formation.

Neutrophils form neutrophil extracellular traps (NETs), which have been implicated in microcirculatory plugging. NET formation (NETosis) involves the fusion of granule and nuclear contents, which are then released in the extracellular space. Myeloperoxidase (MPO) plays a major role in NETosis leading to the dissociation of DNA from histones.

Novel regulator of vasopressin secretion: phoenixin.

The newly described hypothalamic peptide, phoenixin, is produced in the hypothalamus and adenohypophysis, where it acts to control reproductive hormone secretion. Both phoenixin and its receptor GPR173 are expressed in the hypothalamic supraoptic (SON) and paraventricular (PVN) nuclei, suggesting additional, nonreproductive effects of the peptide to control vasopressin (AVP) or oxytocin (OT) secretion. Hypothalamo-neurohypophysial explants released AVP but not OT in response to phoenixin.

A Sall1-NuRD interaction regulates multipotent nephron progenitors and is required for loop of Henle formation.

The formation of the proper number of nephrons requires a tightly regulated balance between renal progenitor cell self-renewal and differentiation. The molecular pathways that regulate the transition from renal progenitor to renal vesicle are not well understood. Here, we show that Sall1interacts with the nucleosome remodeling and deacetylase complex (NuRD) to inhibit premature differentiation of nephron progenitor cells.

Dural arteriovenous fistula-induced thalamic dementia: report of 4 cases.

Nonhemorrhagic neurological deficits are underrecognized symptoms of intracranial dural arteriovenous fistulas (dAVFs) having cortical venous drainage. These symptoms are the consequence of cortical venous hypertension and portend a clinical course with increased risk of neurological morbidity and mortality. One rarely documented and easily misinterpreted type of nonhemorrhagic neurological deficit is progressive dementia, which can result from venous hypertension in the cortex or in bilateral thalami.

Neuronostatin acts via GPR107 to increase cAMP-independent PKA phosphorylation and proglucagon mRNA accumulation in pancreatic α-cells.

Neuronostatin (NST) is a recently described peptide that is produced from the somatostatin preprohormone in pancreatic δ-cells. NST has been shown to increase glucagon secretion from primary rat pancreatic islets in low-glucose conditions. Here, we demonstrate that NST increases proglucagon message in α-cells and identify a potential mechanism for NST's cellular activities, including the phosphorylation of PKA following activation of the G protein-coupled receptor, GPR107.

Clusterin Seals the Ocular Surface Barrier in Mouse Dry Eye.

Dry eye is a common disorder caused by inadequate hydration of the ocular surface that results in disruption of barrier function. The homeostatic protein clusterin (CLU) is prominent at fluid-tissue interfaces throughout the body. CLU levels are reduced at the ocular surface in human inflammatory disorders that manifest as severe dry eye, as well as in a preclinical mouse model for desiccating stress that mimics dry eye.

The Physiology of Proinsulin C-Peptide: Unanswered Questions and a Proposed Model.

C-peptide is produced, processed, and secreted with insulin, and appears to exert separate but intimately related effects. In this review, we address the existence of the C-peptide receptor, the interaction between C-peptide and insulin, and the potential physiological significance of proinsulin C-peptide.

Understanding peptide biology: The discovery and characterization of the novel hormone, neuronostatin.

The Human Genome Project provided the opportunity to use bioinformatic approaches to discover novel, endogenous hormones. Using this approach we have identified two novel peptide hormones and review here our strategy for the identification and characterization of the hormone, neuronostatin. We describe in this mini-review our strategy for determining neuronostatin's actions in brain, heart and pancreas.

The LXR inverse agonist SR9238 suppresses fibrosis in a model of non-alcoholic steatohepatitis.

Objective: Non-alcoholic steatohepatitis (NASH) is characterized by hepatic steatosis, inflammation and fibrosis. There are currently no targeted therapies for NASH. We developed a liver-specific LXR inverse agonist, SR9238, which effectively reduces hepatic lipogenesis in models of obesity and hepatic steatosis.

Neuropathology and genetics of cerebroretinal vasculopathies.

Cerebroretinal vasculopathy (CRV) and the related diseases hereditary endotheliopathy with retinopathy, neuropathy, and stroke (HERNS), hereditary vascular retinopathy (HVR) and hereditary systemic angiopathy (HSA) [subsequently combined as retinovasculopathy and cerebral leukodystrophy (RVCL)] are devastating autosomal-dominant disorders of early to middle-age onset presenting with a core constellation of neurologic and ophthalmologic findings. This family of diseases is linked by specific mutations targeting a core region of a gene. Frameshift mutations in the carboxyl-terminus of three prime exonuclease-1 (TREX1), the major mammalian 3' to 5' DNA exonuclease on chromosome 3p21.

Low O2-induced ATP release from erythrocytes of humans with type 2 diabetes is restored by physiological ratios of C-peptide and insulin.

ATP release from erythrocytes in response to reduced oxygen (O2) tension stimulates local vasodilation, enabling these cells to direct perfusion to areas in skeletal muscle in need of O2. Erythrocytes of humans with type 2 diabetes do not release ATP in response to low O2. Both C-peptide and insulin individually inhibit low O2-induced ATP release from healthy human erythrocytes, yet when coadministered at physiological concentrations and ratios, no inhibition is seen.

Evidence for an interaction between proinsulin C-peptide and GPR146.

Microvascular diseases, such as retinopathies, neuropathies, and nephropathies, are a devastating consequence of type 1 and type 2 diabetes. The etiology of diabetes-associated microvascular dysfunction is poorly understood, and, likewise, treatment modalities for these disorders are limited. Interestingly, proinsulin C-peptide has been shown to play a protective role against diabetes-associated complications in experimental animals and in diabetic humans and is thus an attractive therapeutic target.

Evidence for an interaction between proinsulin C-peptide and GPR146.

Microvascular diseases, such as retinopathies, neuropathies, and nephropathies, are a devastating consequence of type 1 and type 2 diabetes. The etiology of diabetes-associated microvascular dysfunction is poorly understood, and, likewise, treatment modalities for these disorders are limited. Interestingly, proinsulin C-peptide has been shown to play a protective role against diabetes-associated complications in experimental animals and in diabetic humans and is thus an attractive therapeutic target.