Dry eye syndrome is defined as a disorder of the tear film caused by either a decreased production in tears or a disruption to the stability of the complex tear film, which causes damage to the ocular surface. It has been developed the medicine for dry eye syndrome focusing anti-inflammation or mucin secretion, however, no treatment has been developed focusing on the effect of elevation of the lacrimal secretion. We recently identified that pituitary adenylate cyclase-activating polypeptide (PACAP)-null mice develop dry eye-like symptoms such as corneal keratinization and tear reduction. PACAP receptor (PAC1-R) immunoreactivity was observed in the acinar cells of the mouse lacrimal gland. PACAP eye drop significantly stimulated tear secretion level, and the effect was suppressed by pretreatment with PAC1-R antagonist or adenylate cyclase inhibitor. PACAP eye drop on the PACAP KO mouse significantly increased the tear secretion, and continuous eye drop suppressed progression of the corneal keratinization. PACAP eye drops increase aquaporin 5 (AQP5) levels in the membrane of acinar cells in lacrimal glands. AQP5 siRNA treatment significantly attenuates PACAP-induced tear secretion. Based on these results, PACAP might be clinically useful to treat dry eye disorder.
Transfer of lactate from astrocytes to neurons is activated when synaptic activity is increased, and this mechanism is now known as the astrocyte-neuron lactate shuttle (ANLS), that could account for the coupling between synaptic activity and energy delivery. Many lines of evidence suggested that ANLS contributes to neuronal activation or synaptic plasticity at the cellular level as well as learning/memory and cocaine addiction at the behavioral level. However, the candidate neurotransmitters which evoke ANLS activation are still under discussion. Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neurotransmitter which distributed widely in central nervous system. Since PACAP might activate ANLS from very low concentration in cultured forebrain astrocytes, PACAP might be one of the candidates for the endogenous ANLS activator. In the present study, we investigated the potential relevance of PACAP/ANLS signaling in the learning/memory and spinal nociceptive transmission. In this study, we made the following findings: 1) PACAP could be an endogenous inducer for ANLS activation in central nervous system; 2) ANLS activation by PACAP/PAC1 receptor signaling contributed to learning/memory and induced long-lasting nociceptive behaviors; 3) PKC activation played an important role in the PACAP/PAC1 receptor-evoked ANLS.
Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide, and exists diverse physiological functions such as a cell protection, anti-inflammation, and neuronal proliferation and differentiation. There are many evidences that PACAP contributes to the neuronal developmental processes during embryonic periods and after the birth, and that PACAP is involved in the development in ectodermal origin including nervous system. However, few evidences have been reported that PACAP contributes to the development of the other germ layer. In here, we introduced our recent study that PACAP was involved in the hematopoiesis. Moreover, we have showed prospective functions of PACAP on the homeostatic and pathological conditions through the autonomic nerve innervation.
The advent of the genomic era has led to the discovery of linkages of several genes and pathways to schizophrenia and autism spectrum disorder (ASD) that may serve as new biomarkers or therapeutic targets for these diseases. Two large-scale genetic studies published early in 2011 provided evidence that functional microduplications at 7q36.3, containing VIPR2, are a risk factor for schizophrenia. 7q36.3 microduplications were also reported to be significantly increased in ASD. VIPR2 encodes VPAC2, a seven transmembrane heterotrimeric G protein-coupled receptor that binds two homologous neuropeptides with high affinity, PACAP and VIP. These clinical studies demonstrate a VIPR2 genetic linkage to schizophrenia and ASD and should lead to novel insights into the etiology of these mental health disorders. However, the mechanism by which overactive VPAC2 signaling may lead to schizophrenia and ASD is unknown. In the present review, we will describe recent advances in the genetics of schizophrenia and attempt to discuss the pathophysiological role of altered VPAC2 signaling in psychiatric disorders.
Ten years have passed since Yamanaka et al. reported the establishment of human iPS cells, which became one of the triggers to make national efforts in Japan to promote research and translation of regenerative medicine and cell therapy (regenerative medicine etc.). However, it has been unreasonable in many cases to directly apply the existing regulation to cells processed for the purpose of use in regenerative medicine etc., which have quite different properties from conventional pharmaceuticals and medical devices. For this reason, in recent years, drastic reforms of various regulations of medical and pharmaceutical affairs have been vigorously pursued for efficient translation of regenerative medicine etc. Regarding medical affairs, “The Act on the Safety of Regenerative Medicine” was established for the purpose of providing safe regenerative medicine etc. to patients promptly and smoothly, establishing standards for regenerative medicine providing agencies and cell culture processing facilities. Regarding pharmaceutical affairs, a new chapter and an early approval system (conditional/term-limited approval system) for “regenerative medical products”, which consists of cellular and gene therapy products, were introduced into “Pharmaceuticals and Medical Devices Act”, a revised and renamed version of “Pharmaceutical Affairs Law”. In this review article, we overview the current perspectives of regulations and challenges for translation of regenerative medicine etc. in Japan.
Etanercept is a dimeric genetic recombinant glycoprotein consisting of Fc domain of human Immunoglobulin G1 and the extracellular domain of human tumor necrosis factor (TNF) receptor type II. Etanercept exerts therapeutic effects on inflammatory diseases such as rheumatoid arthritis and juvenile idiopathic arthritis by neutralizing biological activities of TNFα/Lymphotoxin (LT) α. Mochida Pharmaceutical and LG Chem have developed syringe, pen, and vial products of Etanercept BS (biosimilar) as the first biosimilar of Enbrel in Japan. The active ingredient of those products “Etanercept biosimilar 1” has the identical primary structure to that of Enbrel. The development of the Etanercept BS, including evaluations of quality attributes, nonclinical and clinical studies was performed in accordance with “Policies on Assurance of Quality, Safety and Efficacy of Biosimilars”. The quality attributes of Etanercept BS were similar to those of Enbrel, and the binding affinities to TNFα/LTα, TNFα neutralizing activity, nonclinical pharmacokinetics and toxicological profiles of Etanercept BS were comparable to Enbrel. Additionally, the pharmacokinetic profile and efficacy of Etanercept BS were equivalent to those of Enbrel and there was no clinically significant difference in safety profiles between them in Phase I and Phase III clinical studies. The marketing approval application of the Etanercept BS with the same indications as Enbrel filed by Mochida Pharmaceutical was approved in January 2018 and the products will be launched by Ayumi Pharmaceutical in the near future. The Etanercept BS, which is as highly effective as Enbrel is expected to make beneficial therapies more easily accessible to patients.