Cardiac Vagal Nerve Activity Increases During Exercise to Enhance Coronary Blood Flow.

BACKGROUND: The phrase complete vagal withdrawal is often used when discussing autonomic control of the heart during exercise. However, more recent studies have challenged this assumption. We hypothesized that cardiac vagal activity increases during exercise and maintains cardiac function via transmitters other than acetylcholine. METHODS: Chronic direct recordings of cardiac vagal nerve activity, cardiac output, coronary artery blood flow, and heart rate were recorded in conscious adult sheep during whole-body treadmill exercise. Cardiac innervation of the left cardiac vagal branch was confirmed with lipophilic tracer dyes (DiO). Sheep were exercised with pharmacological blockers of acetylcholine (atropine, 250 mg), VIP (vasoactive intestinal peptide; [4Cl-D-Phe6,Leu17]VIP 25 µg), or saline control, randomized on different days. In a subset of sheep, the left cardiac vagal branch was denervated. RESULTS: Neural innervation from the cardiac vagal branch is seen at major cardiac ganglionic plexi, and within the fat pads associated with the coronary arteries. Directly recorded cardiac vagal nerve activity increased during exercise. Left cardiac vagal branch denervation attenuated the maximum changes in coronary artery blood flow (maximum exercise, control: 63.5±5.9 mL/min, n=8; cardiac vagal denervated: 32.7±5.6 mL/min, n=6, P=2.5×10-7), cardiac output, and heart rate during exercise. Atropine did not affect any cardiac parameters during exercise, but VIP antagonism significantly reduced coronary artery blood flow during exercise to a similar level to vagal denervation. CONCLUSIONS: Our study demonstrates that cardiac vagal nerve activity actually increases and is crucial for maintaining cardiac function during exercise. Furthermore, our findings show the dynamic modulation of coronary artery blood flow during exercise is mediated by VIP.

Stimulus-specific enhancement in mouse visual cortex requires GABA but not VIP-peptide release from VIP interneurons.

When adult mice are repeatedly exposed to a particular visual stimulus for as little as 1 h per day for several days while their visual cortex (V1) is in the high-gain state produced by locomotion, that specific stimulus elicits much stronger responses in V1 neurons for the following several weeks, even when measured in anesthetized animals. Such stimulus-specific enhancement (SSE) is not seen if locomotion is prevented. The effect of locomotion on cortical responses is mediated by vasoactive intestinal peptide (VIP) positive interneurons, which can release both the peptide and the inhibitory neurotransmitter GABA. Previous studies have examined the role of VIP-ergic interneurons, but none have distinguished the individual roles of peptide from GABA release. Here, we used genetic ablation to determine which of those molecules secreted by VIP-ergic neurons is responsible for SSE. SSE was not impaired by VIP deletion but was prevented by compromising release of GABA from VIP cells. This finding suggests that SSE may result from Hebbian mechanisms that remain present in adult V1.NEW & NOTEWORTHY Many neurons package and release a peptide along with a conventional neurotransmitter. The conventional view is that such peptides exert late, slow effects on plasticity. We studied a form of cortical plasticity that depends on the activity of neurons that express both vasoactive intestinal peptide (VIP) and the inhibitory neurotransmitter GABA. GABA release accounted for their action on plasticity, with no effect of deleting the peptide on this phenomenon.

Targeting the PAC1 receptor mitigates degradation of myelin and synaptic markers and diminishes locomotor deficits in the cuprizone demyelination model.

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system with a strong neuroinflammatory component. Current treatments principally target the immune system but fail to preserve long-term myelin health and do not prevent neurological decline. Studies over the past two decades have shown that the structurally related neuropeptides VIP and PACAP (vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide, respectively) exhibit pronounced anti-inflammatory activities and reduce clinical symptoms in MS disease models, largely via actions on their bivalent VIP receptor type 1 and 2. Here, using the cuprizone demyelination model, we demonstrate that PACAP and VIP, and strikingly the PACAP-selective receptor PAC1 agonist maxadilan, prevented locomotor deficits in the horizontal ladder and open field tests. Moreover, only PACAP and maxadilan were able to prevent myelin deterioration, as assessed by a reduction in the expression of the myelin markers proteolipid protein 1, oligodendrocyte transcription factor 2, quaking-7 (APC) and Luxol Fast Blue staining. Furthermore, PACAP and maxadilan (but not VIP), prevented striatal synaptic loss and diminished astrocyte and microglial activation in the corpus callosum of cuprizone-fed mice. In vitro, PACAP or maxadilan prevented lipopolysaccharide (LPS)-induced polarisation of primary astrocytes at 12-24 h, an effect that was not seen with maxadilan in LPS-stimulated microglia. Taken together, our data demonstrates for the first time that PAC1 agonists provide distinctive protective effects against white matter deterioration, neuroinflammation and consequent locomotor dysfunctions in the cuprizone model. The results indicate that targeting the PAC1 receptor may provide a path to treat myelin-related diseases in humans.

Microglia cells treated with synthetic vasoactive intestinal peptide or transduced with LentiVIP protect neuronal cells against degeneration.

A common pathological hallmark of neurodegenerative disorders is neuronal cell death, accompanied by neuroinflammation and oxidative stress. The vasoactive intestinal peptide (VIP) is a pleiotropic peptide that combines neuroprotective and immunomodulatory actions. The gene therapy field shows long-term promise for treating a wide range of neurodegenerative diseases (ND). In this study, we aimed to investigate the in vitro efficacy of transduction of microglia using lentiviral gene therapy vectors encoding VIP (LentiVIP). Additionally, we tested the protective effects of the secretome derived from LentiVIP-infected "immortalized human" microglia HMC3 cells, and cells treated with Synthetic VIP (SynVIP), against toxin-induced neurodegeneration. First, LentiVIP, which stably expresses VIP, was generated and purified. VIP secretion in microglial conditioned media (MG CM) for LentiVIP-infected HMC3 microglia cells was confirmed. Microglia cells were activated with lipopolysaccharide, and groups were formed as follows: 1) Control, 2) SynVIP-treated, or 3) LentiVIP-transduced. These MG CM were applied on an in vitro neurodegenerative model formed by differentiated (d)-SH-SY5Y cells. Then, cell survival analysis and apoptotic nuclear staining, besides measurement of oxidative/inflammatory parameters in CM of cells were performed. Activated MG CM reduced survival rates of both control and toxin-applied (d)-SH-SY5Y cells, whereas LentiVIP-infected MG CM and SynVIP-treated ones exhibited better survival rates. These findings were supported by apoptotic nuclear evaluations of (d)-SH-SY5Y cells, alongside oxidative/inflammatory parameters in their CM. LentiVIP seems worthy of further studies for the treatment of ND because of the potential of gene therapy to treat diseases effectively with a single injection.

Impact of Postarrest Vasoactive-Inotropic Score on Acute Kidney Injury in Cardiac Arrest Survivors: A Retrospective Cohort Study.

Background: Postarrest acute kidney injury (AKI) is a major health burden because it is associated with prolonged hospitalization, increased dialysis requirement, high mortality, and unfavorable neurological outcomes. Managing hemodynamic instability during the early postarrest period is critical; however, the role of quantified vasopressor dependence in AKI development in relation to illness severity remains unclear. Methods: A retrospective, observational cohort study that enrolled 411 non-traumatic adult cardiac arrest survivors without pre-arrest end-stage kidney disease between January 2017 and December 2019, grouped according to their baseline kidney function. The criteria for kidney injury were based on the Kidney Disease: Improving Global Outcomes definition and AKI staging system. The degree of vasopressor dependence within the first 24 h following return of spontaneous circulation (ROSC) was presented using the maximum vasoactive-inotropic score ( VIS max ). Results: Of the 411 patients, 181 (44%) had early AKI after ROSC. Patients with AKI showed an increased risk of in-hospital mortality (adjusted OR [aOR] 5.40, 95% CI 3.36-8.69, p < 0.001) and unfavorable neurological outcome (aOR 5.70, 95% CI 3.45-9.43, p < 0.001) compared to patients without AKI. The risk of adverse outcomes increased with illness severity. Patients with vasopressor support had an increased risk of early AKI. A low VIS max was associated with AKI stage 1-2 (aOR 2.51, 95% CI 1.20-5.24), whereas a high VIS max was associated with an increased risk for AKI stage 3 (aOR 2.46, 95% CI 1.28-4.75). Conclusions: Early AKI is associated with an increased risk of in-hospital mortality and unfavorable neurologic recovery in cardiac arrest survivors. Postarrest VIS max is an independent predictor of the development and severity of AKI following ROSC, regardless of baseline kidney function.

The Utility of the Vasoactive-Inotropic Score and Its Nomogram in Guiding Postoperative Management in Heart Transplant Recipients.

Background: In the early postoperative stage after heart transplantation, there is a lack of predictive tools to guide postoperative management. Whether the vasoactive-inotropic score (VIS) can aid this prediction is not well illustrated. Methods: In total, 325 adult patients who underwent heart transplantation at our center between January 2015 and December 2018 were included. The maximum VIS (VISmax) within 24 h postoperatively was calculated. The Kaplan-Meier method was used for survival analysis. A logistic regression model was established to determine independent risk factors and to develop a nomogram for a composite severe adverse outcome combining early mortality and morbidity. Results: VISmax was significantly associated with extensive early outcomes such as early death, renal injury, cardiac reoperation and mechanical circulatory support in a grade-dependent manner, and also predicted 90-day and 1-year survival (p < 0.05). A VIS-based nomogram for the severe adverse outcome was developed that included VISmax, preoperative advanced heart failure treatment, hemoglobin and serum creatinine. The nomogram was well calibrated (Hosmer-Lemeshow p = 0.424) with moderate to strong discrimination (C-index = 0.745) and good clinical utility. Conclusion: VISmax is a valuable prognostic index in heart transplantation. In the early post-transplant stage, this VIS-based nomogram can easily aid intensive care clinicians in inferring recipient status and guiding postoperative management.

Assessing the safety of physical rehabilitation in critically ill patients: a Delphi study.

BACKGROUND: Physical rehabilitation of critically ill patients is implemented to improve physical outcomes from an intensive care stay. However, before rehabilitation is implemented, a risk assessment is essential, based on robust safety data. To develop this information, a uniform definition of relevant adverse events is required. The assessment of cardiovascular stability is particularly relevant before physical activity as there is uncertainty over when it is safe to start rehabilitation with patients receiving vasoactive drugs. METHODS: A three-stage Delphi study was carried out to (a) define adverse events for a general ICU cohort, and (b) to define which risks should be assessed before physical rehabilitation of patients receiving vasoactive drugs. An international group of intensive care clinicians and clinician researchers took part. Former ICU patients and their family members/carers were involved in generating consensus for the definition of adverse events. Round one was an open round where participants gave their suggestions of what to include. In round two, participants rated their agreements with these suggestions using a five-point Likert scale; a 70% consensus agreement threshold was used. Round three was used to re-rate suggestions that had not reached consensus, whilst viewing anonymous feedback of participant ratings from round two. RESULTS: Twenty-four multi-professional ICU clinicians and clinician researchers from 10 countries across five continents were recruited. Average duration of ICU experience was 18 years (standard deviation 8) and 61% had publications related to ICU rehabilitation. For the adverse event definition, five former ICU patients and one patient relative were recruited. The Delphi process had a 97% response rate. Firstly, 54 adverse events reached consensus; an adverse event tool was created and informed by these events. Secondly, 50 risk factors requiring assessment before physical rehabilitation of patients receiving vasoactive drugs reached consensus. A second tool was created, informed by these suggestions. CONCLUSIONS: The adverse event tool can be used in studies of physical rehabilitation to ensure uniform measurement of safety. The risk assessment tool can be used to inform clinical practise when risk assessing when to start rehabilitation with patients receiving vasoactive drugs. Trial registration This study protocol was retrospectively registered on https://www.researchregistry.com/ (researchregistry2991).

VPAC2 receptor mediates VIP-potentiated insulin secretion via ion channels in rat pancreatic ß cells.

Vasoactive intestinal peptide (VIP), a small neuropeptide composing of 28 amino acids, functions as a neuromodulator with insulinotropic effect on pancreatic ß cells, in which it is of vital importance in regulating the levels of blood glucose. VIP potently agonizes VPAC2 receptor (VPAC2-R). Agonists of VPAC2-R stimulate glucose-dependent insulin secretion. The purpose of this study was to further investigate the possible ion channel mechanisms in VPAC2-R-mediated VIP-potentiated insulin secretion. The results of insulin secretion experiments showed that VIP augmented insulin secretion in a glucose-dependent manner. The insulinotropic effect was mediated by VPAC2-R rather than VPAC1 receptor (VPAC1-R), through the adenylyl cyclase (AC)/protein kinase A (PKA) signalling pathway. The calcium imaging analysis demonstrated that VIP increased intracellular Ca2+ concentration ([Ca2+]i). In addition, in the whole-cell voltage-clamp mode, we found that VIP blocked the voltage-dependent potassium (Kv) channel currents, while this effect was reversed by inhibiting the VPAC2-R, AC or PKA respectively. Taken together, these findings suggest that VIP stimulates insulin secretion by inhibiting the Kv channels, activating the Ca2+ channels, and increasing [Ca2+]i through the VPAC2-R and AC/PKA signalling pathway. These findings provide theoretical basis for the research of VPAC2-R as a novel therapeutic target.

Effect of perioperative management on early graft function in living donor paediatric kidney transplantation.

BACKGROUND: Paediatric kidney transplantation has an increased risk of surgical and vascular complications, with intensive care monitoring required postoperatively. This study aimed to determine if perioperative management affects early graft function in living donor paediatric kidney transplantation. METHODS: Clinical data was extracted from the electronic medical record for living donor kidney transplants at two paediatric centres covering the state of New South Wales (NSW), Australia from 2009 to 2021. Estimated glomerular filtration rate (eGFR) of 7 days and 1-month post-transplant were calculated as measures of early graft function. RESULTS: Thirty-nine eligible patients (female n (%) 13 (33%)) with a median (IQR) age of 6 (3-9) years and pre-transplant eGFR of 7 (6-10) mL/min/1.73 m2 were analysed. Mean (SD) central venous pressure (CVP) after revascularisation was 11 (4) mmHg. Intraoperatively, mean volume of fluid administered was 84 (39) mL/kg, and 34 (87%) patients received vasoactive agents. Average systolic blood pressure (BP) in the first 24-h post-transplant was 117 (12) mmHg. Postoperatively, median volume of fluid administered in the first 24 h was 224 (159-313) mL/kg, and 17 (44%) patients received vasoactive agents. Median eGFR 7 days and 1-month post-transplant were 115 (79-148) and 103 (83-115) mL/min/1.73 m2, respectively. Linear regression analyses demonstrated that after adjusting for age, the average CVP after revascularisation and average systolic BP in the first 24-h post-transplant were not associated with eGFR in the first month post-transplant. CONCLUSIONS: Targeted intraoperative and postoperative fluid and haemodynamic characteristics were achieved but did not correlate with early graft function.

Influence of polyethylene terephthalate (PET) microplastic on selected active substances in the intramural neurons of the porcine duodenum.

BACKGROUND: Currently, society and industry generate huge amounts of plastics worldwide. The ubiquity of microplastics is obvious, but its impact on the animal and human organism remains not fully understood. The digestive tract is one of the first barriers between pathogens and xenobiotics and a living organism. Its proper functioning is extremely important in order to maintain homeostasis. The aim of this study was to determine the effect of microplastic on enteric nervous system and histological structure of swine duodenum. The experiment was carried out on 15 sexually immature gilts, approximately 8 weeks old. The animals were randomly divided into 3 study groups (n = 5/group). The control group received empty gelatin capsules once a day for 28 days, the first research group received daily gelatin capsules with polyethylene terephthalate (PET) particles as a mixture of particles of various sizes (maximum particle size 300 µm) at a dose of 0.1 g/animal/day. The second study group received a dose ten times higher-1 g/animal/day. RESULTS: A dose of 1 g/day/animal causes more changes in the enteric nervous system and in the histological structure of duodenum. Statistically significant differences in the expression of cocaine and amphetamine regulated transcript, galanin, neuronal nitric oxide synthase, substance P, vesicular acetylcholine transporter and vasoactive intestinal peptide between control and high dose group was noted. The histopathological changes were more frequently observed in the pigs receiving higher dose of PET. CONCLUSION: Based on this study it may be assumed, that oral intake of microplastic might have potential negative influence on digestive tract, but it is dose-dependent.

Perioperative hypotension and use of vasoactive agents in non-cardiac surgery: A scoping review.

BACKGROUND: Perioperative hypotension is common and associated with adverse patient outcomes. Vasoactive agents are often used to manage hypotension, but the ideal drug, dose and duration of treatment has not been established. With this scoping review, we aim to provide an overview of the current body of evidence regarding the vasoactive agents used to treat perioperative hypotension in non-cardiac surgery. METHODS: We included all studies describing the use of vasoactive agents for the treatment of perioperative hypotension in non-cardiac surgery. We excluded literature reviews, case studies, and studies on animals and healthy subjects. We posed the following research questions: (1) in which surgical populations have vasoactive agents been studied? (2) which agents have been studied? (3) what doses have been assessed? (4) what is the duration of treatment? and (5) which desirable and undesirable outcomes have been assessed? RESULTS: We included 124 studies representing 10 surgical specialties. Eighteen different agents were evaluated, predominantly phenylephrine, ephedrine, and noradrenaline. The agents were administered through six different routes, and numerous comparisons between agents, dosages and routes were included. Then, 88 distinct outcome measures were assessed, of which 54 were judged to be non-patient-centred. CONCLUSIONS: We found that studies concerning vasoactive agents for the treatment of perioperative hypotension varied considerably in all aspects. Populations were heterogeneous, interventions and exposures included multiple agents compared against themselves, each other, fluids or placebo, and studies reported primarily non-patient-centred outcomes.

The role of vasoactive intestinal peptide (VIP) in atropine-related inhibition of the progression of myopia.

OBJECTIVE: This study aimed to investigate the potential involvement of vasoactive intestinal polypeptide (VIP) in myopia development and its contribution to the mechanism of action of the anti-myopia drug, atropine. METHODS: Thirty-three-week-old guinea pigs were randomly divided into normal control (NC, n = 10), monocularly form-deprived (FDM, n = 10), and FDM treated with 1% atropine (FDM + AT, n = 10) groups. The diopter and axial length were measured at 0, 2, and 4 weeks. Guinea pig eyeballs were removed at week four, fixed, and stained for morphological changes. Immunohistochemistry (IHC) and in situ hybridization (ISH) were performed to evaluate VIP protein and mRNA levels. RESULTS: The FDM group showed an apparent myopic shift compared to the control group. The results of the H&E staining were as follows: the cells of the inner/outer nuclear layers and retinal ganglion cells were disorganized; the choroidal thickness (ChT), blood vessel lumen, and area were decreased; the sclera was thinner, with disordered fibers and increased interfibrillar space. IHC and ISH revealed that VIP's mRNA and protein expressions were significantly up-regulated in the retina of the FDM group. Atropine treatment attenuated FDM-induced myopic shift and fundus changes, considerably reducing VIP's mRNA and protein expressions. CONCLUSIONS: The findings of elevated VIP mRNA and protein levels observed in the FDM group indicate the potential involvement of VIP in the pathogenesis and progression of myopia. The ability of atropine to reduce this phenomenon suggests that this may be one of the molecular mechanisms for atropine to control myopia.

Availability and threshold of the vasoactive-inotropic score for predicting early extubation in adults after rheumatic heart valve surgery: a single-center retrospective cohort study.

BACKGROUND: Early extubation (EEx) is defined as the removal of the endotracheal tube within 8 h postoperatively. The present study involved determining the availability and threshold of the vasoactive-inotropic score (VIS) for predicting EEx in adults after elective rheumatic heart valve surgery. METHODS: The present study was designed as a single-center retrospective cohort study which was conducted with adults who underwent elective rheumatic heart valve surgery with CPB. The highest VIS in the immediate postoperative period was used in the present study. The primary outcome, the availability of VIS for EEx prediction and the optimal threshold value were determined using ROC curve analysis. The gray zone analysis of the VIS was performed by setting the false negative or positive rate R = 0.05, and the perioperative risk factors for prolonged EEx were identified by multivariate logistic analysis. The postoperative complications and outcomes were compared between different VIS groups. RESULTS: Among the 409 patients initially screened, 379 patients were ultimately included in the study. The incidence of EEx was determined to be 112/379 (29.6%). The VIS had a good predictive value for EEx (AUC = 0.864, 95% CI: [0.828, 0.900], P < 0.001). The optimal VIS threshold for EEx prediction was 16.5, with a sensitivity of 71.54% (65.85-76.61%) and a specificity of 88.39% (81.15-93.09%). The upper and lower limits of the gray zone for the VIS were determined as (12, 17.2). The multivariate logistic analysis identified age (OR, 1.060; 95% CI: 1.017-1.106; P = 0.006), EF% (OR, 0.798; 95% CI: 0.742-0.859; P < 0.001), GFR (OR, 0.933; 95% CI: 0.906-0.961; P < 0.001), multiple valves surgery (OR, 4.587; 95% CI: 1.398-15.056; P = 0.012), and VIS > 16.5 (OR, 12.331; 95% CI: 5.015-30.318; P < 0.001) as the independent risk factors for the prolongation of EEx. The VIS ≤ 16.5 group presented a greater success rate for EEx, a shorter invasive ventilation support duration, and a lower incidence of complications than did the VIS > 16.5 group, while the incidence of reintubation was similar between the two groups. CONCLUSION: In adults, after elective rheumatic heart valve surgery, the highest VIS in the immediate postoperative period was a good predictive value for EEx, with a threshold of 16.5.

Differential Expression of PACAP/VIP Receptors in the Post-Mortem CNS White Matter of Multiple Sclerosis Donors.

Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) are two neuroprotective and anti-inflammatory molecules of the central nervous system (CNS). Both bind to three G protein-coupled receptors, namely PAC1, VPAC1 and VPAC2, to elicit their beneficial effects in various CNS diseases, including multiple sclerosis (MS). In this study, we assessed the expression and distribution of PACAP/VIP receptors in the normal-appearing white matter (NAWM) of MS donors with a clinical history of either relapsing-remitting MS (RRMS), primary MS (PPMS), secondary progressive MS (SPMS) or in aged-matched non-MS controls. Gene expression studies revealed MS-subtype specific changes in PACAP and VIP and in the receptors' levels in the NAWM, which were partly corroborated by immunohistochemical analyses. Most PAC1 immunoreactivity was restricted to myelin-producing cells, whereas VPAC1 reactivity was diffused within the neuropil and in axonal bundles, and VPAC2 in small vessel walls. Within and around lesioned areas, glial cells were the predominant populations showing reactivity for the different PACAP/VIP receptors, with distinctive patterns across MS subtypes. Together, these data identify the differential expression patterns of PACAP/VIP receptors among the different MS clinical entities. These results may offer opportunities for the development of personalized therapeutic approaches to treating MS and/or other demyelinating disorders.

Differences in Neuropathology between Nitroglycerin-Induced Mouse Models of Episodic and Chronic Migraine.

Multiple animal models of migraine have been used to develop new therapies. Understanding the transition from episodic (EM) to chronic migraine (CM) is crucial. We established models mimicking EM and CM pain and assessed neuropathological differences. EM and CM models were induced with single NTG or multiple injections over 9 days. Mechanical hypersensitivity was assessed. Immunofluorescence utilized c-Fos, NeuN, and Iba1. Proinflammatory and anti-inflammatory markers were analyzed. Neuropeptides (CGRP, VIP, PACAP, and substance P) were assessed. Mechanical thresholds were similar. Notable neuropathological distinctions were observed in Sp5C and ACC. ACC showed increased c-Fos and NeuN expression in CM (p < 0.001) and unchanged in EM. Sp5C had higher c-Fos and NeuN expression in EM (p < 0.001). Iba1 was upregulated in Sp5C of EM and ACC of CM (p < 0.001). Proinflammatory markers were strongly expressed in Sp5C of EM and ACC of CM. CGRP expression was elevated in both regions and was higher in CM. VIP exhibited higher levels in the Sp5C of EM and ACC of CM, whereas PACAP and substance P were expressed in the Sp5C in both models. Despite similar thresholds, distinctive neuropathological differences in Sp5C and ACC between EM and CM models suggest a role in the EM to CM transformation.

Effects of the Neuropeptides Pituitary Adenylate Cyclase Activating Polypeptide and Vasoactive Intestinal Peptide in Male Fertility.

Background and Objectives: The neuroendocrine system plays a crucial role in regulating various bodily functions, including reproduction, with evidence suggesting its significant involvement in male fertility and sperm development. Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase activating polypeptide (PACAP) are expressed in both male and female reproductive tissues, influencing penile erection and regulating steroidogenesis in males. Therefore, our study aimed to compare the protein levels of VIP and PACAP in seminal plasma between healthy controls and sub-fertile patients. Additionally, we sought to correlate the levels of these biomarkers with clinical, functional, and laboratory findings in the participants. Materials and Methods: The study included a total of 163 male participants for analysis. The participants were further stratified into subgroups of fertile and sub-fertile men of four subgroups according to the 2021 WHO guidelines. Seminal plasma concentrations of the neuropeptides VIP and PACAP were measured using human enzyme-linked immunosorbent assay technique. Results: The findings showed statistically significant differences in total sperm count, sperm concentration, total motility, and vitality (p < 0.001) between the fertile group and the sub-fertile group. Specifically, significant differences found between healthy males and oligoasthenospermic patients (p = 0.002), and between asthenospermic and oligoasthenospermic patients (p = 0.039). An ROC analysis showed associated sensitivity and specificity values of 62.2% and 55.6%, respectively, to PACAP seminal levels differentiated between sub-fertile patients from fertile males (p = 0.028). No significant difference in seminal levels of VIP was found between the sub-fertile and fertile groups. Conclusions: Previous research leads to the point of PACAP active involvement in spermatogenesis. In accordance to our study, in human semen samples, we have seen a significance change in PACAP levels amongst patients with low sperm count or with both low sperm count and low motility, hinting at its contribution and acting as a possible factor in this complex process. Thus, alterations in the levels or actions of these neuropeptides have been associated with certain reproductive disorders in males.

The role of vasoactive peptides in skin homeostasis-focus on adiponectin and the kallikrein-kinin system.

Vasoactive peptides often serve a multitude of functions aside from their direct effects on vasodynamics. This article will review the existing literature on two vasoactive peptides and their involvement in skin homeostasis: adiponectin and-as the main representative of the kallikrein-kinin system-bradykinin. Adiponectin is the most abundantly expressed adipokine in the human organism, where it is mainly localized in fat depots including subcutaneous adipose tissue, from where adiponectin can exert paracrine effects. The involvement of adiponectin in skin homeostasis is supported by a number of studies reporting the effects of adiponectin in isolated human keratinocytes, sebocytes, fibroblasts, melanocytes, and immune cells. Regarding skin pathology, the potential involvement of adiponectin in psoriasis, atopic dermatitis, scleroderma, keloid, and melanogenesis is discussed in this article. The kallikrein-kinin system is composed of a variety of enzymes and peptides, most of which have been identified to be expressed in the skin. This also includes the expression of bradykinin receptors on most skin cells. Bradykinin is one of the very few hormones that is targeted by treatment in routine clinical use in dermatology-in this case for the treatment of hereditary angioedema. The potential involvement of bradykinin in wound healing, psoriasis, and melanoma is further discussed in this article. This review concludes with a call for additional preclinical and clinical studies to further explore the therapeutic potential of adiponectin supplementation (for psoriasis, atopic dermatitis, wound healing, scleroderma, and keloid) or pharmacological interference with the kallikrein-kinin system (for wound healing, psoriasis, and melanoma).

Targeting first trimester trophoblast cell metabolism modulates its susceptibility to Zika virus infection.

In the last 15 years Zika virus (ZIKV) caused several outbreaks of increasing scale in Micronesia, South Pacific islands, and more recently in the Caribbean and South America. The severity of the clinical presentation in neonates from pregnant women infected with ZIKV during the last outbreak supports the relevance of unraveling the mechanism of infection and viral persistence in the placenta with local viral isolates. Here, we investigated the relevance of trophoblast metabolic rewiring for viral multiplication and the role of the vasoactive intestinal peptide (VIP) as an endogenous factor associated with placental restriction to ZIKV infection at early pregnancy. Our in vitro model demonstrated that ZIKV triggers metabolic rewiring in first trimester cytotrophoblast-derived cells by increasing glucose utilization as fuel to sustain its replication, decreasing long-chain polyunsaturated fatty acid uptake, and promoting lipid droplets accumulation to favor its multiplication. Of note, variations in nutrient availability modulated viral spread in trophoblast cultures. The presence of VIP during trophoblast infection impaired ZIKV infective particle production and viral replication, restoring cell migration and metabolism. Moreover, the blockade of endogenous VIP signaling increased viral particle production and the viral entry receptor AXL expression. These results highlight the potential role of VIP as an endogenous antiviral factor related to trophoblast cell permissiveness to ZIKV infection at early pregnancy.

Associations of Iron Sucrose and Intradialytic Blood Pressure.

RATIONALE & OBJECTIVE: Intradialytic hypotension and intradialytic hypertension are associated with morbidity and mortality in hemodialysis (HD). Many factors can contribute to intra-HD blood pressure (BP) changes, such as drugs with vasoactive properties that can destabilize an already tenuous BP. Intravenous iron sucrose is commonly administered to correct iron deficiency; however, its reported associations with altered hemodynamics have not been consistent. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 950 outpatients receiving maintenance HD. EXPOSURE: Iron sucrose administered during HD. OUTCOME: Intradialytic hypotension, intradialytic hypertension, systolic blood pressure parameters. ANALYTICAL APPROACH: Unadjusted and adjusted Poisson and linear repeated measures regression models. RESULTS: The mean age of patients included in the study was 53±22 years, 43% were female, and 38% were Black. Mean pre-HD SBP was 152±26 (SD) mm Hg. At baseline, the patients who received higher doses of iron sucrose tended to have diabetes, have longer HD sessions, and have a higher frequency of erythropoiesis-stimulating agent use, compared with those who did not receive iron sucrose. In adjusted models, higher doses of iron sucrose were associated with an 11% lower rate of intradialytic hypotension (incidence rate ratio [IRR] for iron sucrose≥100mg vs 0 mg, 0.89 [95% CI, 0.85-0.94]). In adjusted analyses, the administration of higher doses of iron sucrose during HD was associated with intradialytic hypertension (IRR for iron sucrose≥100mg vs 0 mg, 1.07 [95% CI, 1.04-1.10]). LIMITATIONS: Nonavailability of the precise iron sucrose formulation (volume), laboratory data for each HD session, and outpatient medications. Objective measures of volume status, home medications, and symptom data were not recorded in this study. CONCLUSIONS: We observed an independent association of intravenous iron sucrose administration during HD with a lower risk of intradialytic hypotension and higher risk of intradialytic hypertension. Future studies to better understand the mechanisms underlying these associations are warranted. PLAIN-LANGUAGE SUMMARY: Intradialytic hypotension and intradialytic hypertension are common among patients on hemodialysis, and they are associated with morbidity and mortality. Although many factors may contribute to these risks, medications administered during hemodialysis play an important role. We studied the significance of the intravenous iron sucrose used to treat iron deficiency and the impact it may have on blood pressure during dialysis. In our study of 950 outpatient hemodialysis patients, we observed that administration of iron sucrose was associated with higher systolic blood pressure (during and after hemodialysis sessions) as well as a lower risk of intradialytic hypotension. We also observed that higher doses of iron sucrose are associated with the development of intradialytic hypertension.

Novel bisdemethoxycurcumin@phytomicelle ophthalmic solution: In vitro formulation appraisal and in vivo prompting rapid corneal wound healing evaluations.

A simple and novel phytochemical-based nano-ophthalmic solution was developed for the treatment of eye diseases. This nanoformulation was produced from the mixture of the phytochemicals glycyrrhizin and alpha-glycosyl hesperidin, which serve as the phytonanomaterials that solubilize bisdemethoxycurcumin (BDMC), a promising phytochemical with strong pharmacological activities but with poor water solubility. This novel nanoformulation is a clear solution named as BDMC@phytomicelle ophthalmic solution, which was formulated using a simple preparation process. The BDMC@phytomicelles were characterized by a BDMC encapsulation efficiency of 98.37% ± 2.26%, a small phytomicelle size of 4.06 ± 0.22 nm, and a small polydispersity index of 0.25 ± 0.04. With the optimization of the BDMC@phytomicelles, the apparent solubility of BDMC (i.e., the loading of BDMC in the phytomicelles) in the simulated lacrimal fluid was 3.19 ± 0.02 mg/ml. The BDMC@phytomicelle ophthalmic solution demonstrated a good storage stability. Moreover, it did not cause irritations in rabbit eyes, and it facilitated the excellent corneal permeation of BDMC in mice. The BDMC@phytomicelles demonstrated a marked effect on the in vivo induction of corneal wound healing both in healthy and denervated corneas, as seen in the induction of corneal epithelial wound healing, recovery of corneal sensitivity, and increase in corneal subbasal nerve fiber density. These strong pharmacological activities involve the inhibition of hmgb1 signaling and the induction of VIP signaling. Overall, the BDMC@phytomicelle ophthalmic solution is a novel and promising simple ocular nano-formulation of BDMC with significantly improved in vivo profiles.