Vascular aging encompasses structural and functional changes in the vasculature, significantly contributing to cardiovascular diseases, which are the leading cause of death globally. The incidence and prevalence of these diseases increase with age, with most morbidity and mortality attributed to myocardial infarction and stroke. Diagnosing and intervening in vascular aging while understanding the mechanisms behind age-induced vascular phenotypic and pathophysiological alterations offers the potential for delaying and preventing cardiovascular mortality in an aging population. This review delves into various aspects of vascular aging by examining age-related changes in arterial health at the cellular level, including endothelial dysfunction, cellular senescence, and vascular smooth muscle cell transdifferentiation, as well as at the structural level, including arterial stiffness and changes in wall thickness and diameter. We also explore aging-related changes in perivascular adipose tissue deposition, arterial collateralization, and calcification, providing insights into the physiological and pathological implications. Overall, aging induces phenotypic changes that augment the vascular system’s susceptibility to disease, even in the absence of traditional risk factors, such as hypertension, diabetes, obesity, and smoking. Overall, age-related modifications in cellular phenotype and molecular homeostasis increase the vulnerability of the arterial vasculature to structural and functional alterations, thereby accelerating cardiovascular risk. Increasing our understanding of these modifications is crucial for success in delaying or preventing cardiovascular diseases. Non-invasive techniques, such as measuring carotid intima-media thickness, pulse wave velocity, and flow-mediated dilation, as well as detecting vascular calcifications, can be used for the early detection of vascular aging. Targeting specific pathological mechanisms, such as cellular senescence and enhancing angiogenesis, holds promise for innovative therapeutic approaches.

Background and Purpose: Oxaliplatin is a platinum‐based chemotherapeutic drug used as a first‐line therapy for colorectal cancer. However, its use is associated with severe gastrointestinal side‐effects resulting in dose limitations and/or cessation of treatment. In this study, we tested whether oxidative stress, caused by chronic oxaliplatin treatment, induces enteric neuronal damage and colonic dysmotility.Experimental Approach: Oxaliplatin (3 mg·kg⁻¹ per day) was administered in vivo to Balb/c mice intraperitoneally three times a week. The distal colon was collected at day 14 of treatment. Immunohistochemistry was performed in wholemount preparations of submucosal and myenteric ganglia. Neuromuscular transmission was studied by intracellular electrophysiology. Circular muscle tone was studied by force transducers. Colon propulsive activity studied in organ bath experiments and faeces were collected to measure water content.Key Results: Chronic in vivo oxaliplatin treatment resulted in increased formation of reactive oxygen species (O₂ˉ), nitration of proteins, mitochondrial membrane depolarisation resulting in the release of cytochrome c, loss of neurons, increased inducible NOS expression and apoptosis in both the submucosal and myenteric plexuses of the colon. Oxaliplatin treatment enhanced NO‐mediated inhibitory junction potentials and altered the response of circular muscles to the NO donor, sodium nitroprusside. It also reduced the frequency of colonic migrating motor complexes and decreased circular muscle tone, effects reversed by the NO synthase inhibitor, Nω‐Nitro‐L‐arginine.Conclusion and Implications: Our study is the first to provide evidence that oxidative stress is a key player in enteric neuropathy and colonic dysmotility leading to symptoms of chronic constipation observed in oxaliplatin‐treated mice.

BACKGROUND AND PURPOSE The rostral ventrolateral medulla (RVLM) maintains sympathetic nerve activity (SNA), and integrates adaptive reflexes. Orexin A‐immunoreactive neurones in the lateral hypothalamus project to the RVLM. Microinjection of orexin A into RVLM increases blood pressure and heart rate. However, the expression of orexin receptors, and effects of orexin A in the RVLM on splanchnic SNA (sSNA), respiration and adaptive reflexes are unknown.EXPERIMENTAL APPROACH The effect of orexin A on baseline cardio‐respiratory variables as well as the somato‐sympathetic, baroreceptor and chemoreceptor reflexes in RVLM were investigated in urethane‐anaesthetized, vagotomized and artificially ventilated male Sprague‐Dawley rats (n= 50). orexin A and its receptors were detected with fluorescence immunohistochemistry.KEY RESULTS Tyrosine hydroxylase‐immunoreactive neurones in the RVLM were frequently co‐localized with orexin 1 (OX₁) and orexin 2 (OX₂) receptors and closely apposed to orexin A‐immunoreactive terminals. Orexin A injected into the RVLM was pressor and sympatho‐excitatory. Peak effects were observed at 50 pmol with increased mean arterial pressure (42 mmHg) and SNA (45%). Responses to orexin A (50 pmol) were attenuated by the OX₁ receptor antagonist, SB334867, and reproduced by the OX₂ receptor agonist, [Ala¹¹, D‐Leu¹⁵]orexin B. Orexin A attenuated the somato‐sympathetic reflex but increased baroreflex sensitivity. Orexin A increased or reduced sympatho‐excitation following hypoxia or hypercapnia respectively.CONCLUSIONS AND IMPLICATIONS Although central cardio‐respiratory control mechanisms at rest do not rely on orexin, responses to adaptive stimuli are dramatically affected by the functional state of orexin receptors.

To investigate the phytochemical screening (group determination) and selected pharmacological activities (antioxidant, antimicrobial and analgesic activity) of the plant Sida cordifolia Linn (S. cordifolia). Eighty percent concentrated ethanol extract of the roots was used. To identify the chemical constituents of plant extract standard procedures were followed. In phytochemical screening the crude extract was tested for the presence of different chemical groups like reducing sugar, tannins, saponins, steroids, flavonoids, gums, alkaloids and glycosides. The antioxidant property of ethanolic extract of S. cordifolia was assessed by DPPH free radical scavenging activity. Analgesic activity of the extract was tested using the model of acetic acid induced writhing in mice. Diclofenac sodium is used as reference standard drug for the analgesic activity test. Antibacterial activity of plant extract was carried out using disc diffusion method with five pathogenic bacteria comparison with kanamycin as a standard. Phytochemical analysis of the ethanolic extract of the roots of S. cordifolia indicated the presence of reducing sugar, alkaloids, steroids and saponins. In DPPH scavenging assay the IC50 value was found to be 50 μg/mL which was not comparable to the standard ascorbic acid. The crude extract produced 44.30% inhibition of writhing at the dose of 500 mg/kg body weight which is statistically significant (P>0.001). The in vitro antimicrobial activity of the ethanol extract of the roots of S. cordifolia showed no antimicrobial activity against five types of microorganisms. The experiment was conducted only with five species of bacteria as test species, which do not at all indicate the total inactivity against micro-organisms. The obtained results provide a support for the use of this plant in traditional medicine but further pharmacological studies are required.

The Winnie mouse, carrying a missense mutation in Muc2, is a model for chronic intestinal inflammation demonstrating symptoms closely resembling inflammatory bowel disease (IBD). Alterations to the immune environment, morphological structure, and innervation of Winnie mouse colon have been identified; however, analyses of intestinal transit and colonic functions have not been conducted. In this study, we investigated in vivo intestinal transit in radiographic studies and in vitro motility of the isolated colon in organ bath experiments. We compared neuromuscular transmission using conventional intracellular recording between distal colon of Winnie and C57BL/6 mice and smooth muscle contractions using force displacement transducers. Chronic inflammation in Winnie mice was confirmed by detection of lipocalin-2 in fecal samples over 4 wk and gross morphological damage to the colon. Colonic transit was faster in Winnie mice. Motility was altered including decreased frequency and increased speed of colonic migrating motor complexes and increased occurrence of short and fragmented contractions. The mechanisms underlying colon dysfunctions in Winnie mice included inhibition of excitatory and fast inhibitory junction potentials, diminished smooth muscle responses to cholinergic and nitrergic stimulation, and increased number of α-smooth muscle actin-immunoreactive cells. We conclude that diminished excitatory responses occur both prejunctionally and postjunctionally and reduced inhibitory purinergic responses are potentially a prejunctional event, while diminished nitrergic inhibitory responses are probably due to a postjunction mechanism in the Winnie mouse colon. Many of these changes are similar to disturbed motor functions in IBD patients indicating that the Winnie mouse is a model highly representative of human IBD. NEW & NOTEWORTHY This is the first study to provide analyses of intestinal transit and whole colon motility in an animal model of spontaneous chronic colitis. We found that cholinergic and purinergic neuromuscular transmission, as well as the smooth muscle cell responses to cholinergic and nitrergic stimulation, is altered in the chronically inflamed Winnie mouse colon. The changes to intestinal transit and colonic function we identified in the Winnie mouse are similar to those seen in inflammatory bowel disease patients.