Overview
Vasoactive intestinal peptide, commonly referred to as VIP, is a naturally occurring neuropeptide and peptide hormone found across a wide range of species, including humans, and the synthetic porcine form carries the CAS number 37221-79-7. It is a 28-amino acid peptide that belongs to the secretin/glucagon superfamily and is produced in various tissues, including the gut, pancreas, and nervous system. VIP is classified as a neuropeptide and vasoactive agent, meaning it has been observed in research settings to interact with a variety of biological systems, including immune, cardiovascular, and neurological pathways. With a molecular weight of approximately 3326.8 Da and the formula C147H237N43O43S, it is a relatively well-characterized peptide that has been the subject of numerous preclinical and laboratory studies. VIP is available for research purposes only and is not intended for human use or consumption.
Research & Bioactivity
Vasoactive intestinal peptide (VIP) is a 28-amino acid neuropeptide that researchers have studied extensively for its roles in neuroendocrine signaling, immune modulation, and smooth muscle regulation. Studies have examined VIP's interactions with specific G protein-coupled receptors, particularly VPAC1 and VPAC2, in both in vitro cell culture systems and animal models, with research investigating how receptor binding influences intracellular signaling cascades. Researchers have also explored VIP's presence and function within the central and peripheral nervous systems, including its potential role in circadian rhythm regulation and neuroinflammatory processes observed in rodent studies. Additional research has investigated VIP's effects on immune cell behavior, including modulation of cytokine profiles in preclinical models of inflammatory conditions. The peptide has further been studied in the context of gastrointestinal physiology, where animal and in vitro research has examined its influence on intestinal motility and secretion.
Published Research
The cellular correlates and adolescent reorganisation of cortical myelination networks in the common marmoset.
Hutchings ED, Sawiak SJ, Smith RL, Bethlehem RAI, Roberts AC, et al. — 2026
Structural similarity provides a powerful framework for measuring coordinated macro- and micro-structural variation across the cortex of a single brain. Similarity networks derived from myelin-sensitive MRI sequences undergo marked reorganisation during adolescence, linked to adversity exposure and behavioural outcomes in humans and rodents. However, the cellular mechanisms of MRI similarity and its development in non-human primate cortex remain unexplored. Here, we use myelin-sensitive T1w/T2w ratio images from a cross-sectional sample of 446 common marmosets (aged 0.62 to 12.75 years) to estimate MIND (Morphometric INverse Divergence) as a measure of myelination similarity in individual animals. We find that MIND metrics of myelination similarity are highly correlated with spatial gene expression of myelin basic protein (MBP) and other genes enriched in glutamatergic neurons and PV+ and VIP+ interneurons, reflecting the activity dependence of myelination. Across adolescence, network phenotypes accurately predict animal age and reproducibly capture an axis of myeloarchitectonic maturation spanning primary to transmodal association cortices, consistent with patterns observed in humans. Similarity mapping is a biologically validated and technically reliable measure of cortical myelination networks that can advance our understanding of phylogenetically conserved patterns of myelination network development in the marmoset cortex.
Sustainable stabilization of expansive soils for slope applications using enzyme-induced carbonate precipitation and iron ore tailings.
Mehmood M, Nie W, Gao J, Liu Y, Alshawmar F, et al. — 2026
Expansive soils exhibit pronounced swelling-shrinkage behavior, low shear strength, and high moisture sensitivity, posing significant challenges to the stability of geotechnical structures such as embankments and tailings dam slopes. In this study, a sustainable stabilization strategy integrating enzyme-induced carbonate precipitation (EICP) with iron ore tailings is investigated to improve the hydro-mechanical performance of expansive soils. A comprehensive experimental program was conducted to evaluate changes in unconfined compressive strength (UCS), swelling pressure (Ps), hydraulic conductivity (Ks), cohesion (c), and internal friction angle (φ). Microstructural characterization using scanning electron microscopy and X-ray diffraction was performed to examine calcium carbonate precipitation and its cementation effects within the soil matrix. The results demonstrate that the combined EICP-iron ore tailings treatment significantly enhances soil performance, with UCS, c, and φ increasing by approximately 113%, 48%, and 98%, respectively, while Ps and Ks decrease by approximately 98% and 69%. Furthermore, seepage and slope stability analysis using GeoStudio (SEEP/W and SLOPE/W) indicate that the stabilized soil achieves a markedly higher factor of safety (FoS = 1.896) compared to untreated soils. The findings confirm that the synergistic integration of EICP and iron ore tailings provides an effective, environmentally sustainable, and engineering-feasible solution for stabilizing expansive soils and improving slope performance in tailings dam applications.
Mesenchymal stem cell-derived small extracellular vesicles suppress pyroptosis by delivering miR-125a-5p to improve acute kidney injury in sepsis.
Chen F, Tang TT, Chen ZQ, Yang Q, Zhang Y, et al. — 2026
Sepsis-induced acute kidney injury (S-AKI) is a life-threatening condition driven by excessive immune inflammation, and effective treatments remain lacking. Mesenchymal stem cell-derived small extracellular vesicles (MSC-sEV) have been demonstrated to possess potent immunomodulatory activity. This study aimed to investigate the role and underlying mechanism of MSC-sEV in S-AKI. We established in vivo and in vitro models of S-AKI and employed techniques such as small RNA sequencing, transcriptome sequencing, luciferase reporter assays, and engineered gene editing to validate therapeutic efficacy and elucidate mechanisms. Results demonstrated that in S-AKI, MSC-sEV homed to injured kidneys and were internalized by renal tubular epithelial cells, significantly ameliorating renal damage and improving survival rates. Mechanistically, MSC-sEV delivered miR-125a-5p to target and inhibit TNFR2 expression, thereby blocking TNF-driven pyroptosis mediated by the NF-κB/NLRP3 signaling pathway. Furthermore, engineered modification with the EXOMotif GGAG significantly enhanced MSC-sEV delivery of miR-125a-5p and inhibition of TNFR2. In conclusion, this study demonstrates that MSC-sEV represent a promising drug delivery vehicle with substantial targeted therapeutic potential for S-AKI.
Red Clover Isoflavones plus Urea for Partial Soybean Meal Substitution: Implications for Productivity and Nitrogen Utilization in Holstein cows.
Xiong Z, Hu Y, Zhang S, Wang D, Zheng N, et al. — 2026
Red clover extract (RCE) is rich in isoflavones, which have been reported to improve nitrogen utilization in dairy diets. Therefore, the objective of this study was to evaluate the effects of partially replacing soybean meal (SBM) with RCE plus feed-grade urea on lactation performance and nitrogen metabolism in lactating Holstein cows, relative to a slow-release urea (SRU) nitrogen source formulated to provide a similar amount of dietary nitrogen. In a randomized complete block design, 600 cows received one of 3 diets for 35 d (n = 200 per diet): SBM (10.81% SBM), SRU (0.65% SRU replacing 37.74% of SBM), or RCE (0.20% RCE + 0.57% urea replacing 37.74% of SBM). Diets were formulated to be isoenergetic and isonitrogenous. Data were analyzed using a mixed model with diet as a fixed effect and block and pen nested within diet as random effects; the pen was considered the experimental unit. Milk yield and milk composition did not differ between RCE and SBM. DMI and feed efficiency were similar between these treatments, whereas SRU was associated with greater DMI and lower feed efficiency relative to SBM. Compared with SBM, RCE increased urinary purine derivatives and estimated microbial N, whereas concentrations of urea N in milk, plasma, and urine did not differ. Apparent NDF and ADF digestibility were similar between RCE and SBM but were lower with SRU. Differences among diets were also observed in selected blood biochemical and endocrine variables. These findings indicate that, during the 35-d experimental period, partial replacement of SBM with RCE plus urea maintained lactation performance relative to SBM and was associated with higher estimated microbial N compared with SBM, whereas responses to SRU differed in several nitrogen-related measures.
Associations of grip strength and muscle mass with incident complications in patients with type 2 diabetes: a prospective cohort study.
Ding Y, Sheng W, Shi J, Zhang Z, Yu Y, et al. — 2026
BACKGROUND: Declines in muscle strength and mass are common in individuals with type 2 diabetes (T2D) and are associated with adverse clinical outcomes. However, it remains unclear whether muscle strength or muscle mass provides better prognostic information in this population. This study aimed to examine the associations of grip strength and muscle mass with incident complications in patients with T2D. METHODS: This prospective cohort study included 10,844 participants with T2D who were free of complications at baseline from the UK Biobank. Grip strength was assessed using a Jamar J00105 hydraulic hand dynamometer, and skeletal muscle mass was estimated via bioelectrical impedance analysis using the Janssen equation. Both grip strength and muscle mass were categorized into sex-specific tertiles. Cox proportional hazards models were applied to examine their associations with the risk of 12 incident complications. RESULTS: During a median follow-up of 13.2 years, a total of 11,373 incident complications were recorded. Compared to the high grip strength group, low grip strength was significantly associated with increased risks of coronary artery disease (HR = 1.23, 95% CI 1.10-1.37), heart failure (HR = 1.35, 1.13-1.60), peripheral arterial disease (HR = 1.33, 1.03-1.73), dementia (HR = 1.54, 1.09-2.16), diabetic kidney disease (HR = 1.39, 1.21-1.58), diabetic neuropathy (HR = 1.57, 1.25-1.96), diabetic retinopathy (HR = 1.26, 1.09-1.46), chronic obstructive pulmonary disease (HR = 1.57, 1.29-1.90), steatotic liver disease (HR = 1.43, 1.13-1.82), and osteoporosis (HR = 1.84, 1.37-2.47). A significant interaction between grip strength and sex was observed, with the inverse association between grip strength and coronary artery disease risk being stronger in women than in men. In contrast, compared to the high muscle mass group, low muscle mass was associated with an increased risk of chronic obstructive pulmonary disease only (HR = 1.40, 1.11-1.76). CONCLUSIONS: Lower grip strength is associated with an increased risk of a wide range of incident diabetes-related complications, and its predictive value is superior to that of muscle mass. Future studies should evaluate whether interventions aimed at improving muscle strength can reduce the incidence of these complications among individuals with T2D.