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Neurovascular coupling in the basolateral amygdala modulates negative emotions.

Emotion induces changes in regional cerebral blood flow, a manifestation of neurovascular coupling (NVC). However, whether NVC provides feedback to actively modulate emotion remains unexplored. Here, we demonstrate that NVC actively and bidirectionally modulates stress-induced negative emotions. We established bidirectional manipulations of NVC in freely moving mice by employing integrated pharmacological, genetic, and arteriolar optogenetic approaches. Our results showed that both systemic and region-specific NVC deficiencies in the basolateral amygdala (BLA) heightened emotional responses when mice transitioned from a safe, familiar environment to anxiogenic environments and that local restoration of NVC in the BLA normalized these responses. Mechanistically, NVC dysfunction impaired the capacity of BLA neuronal scaling during state transitions, manifesting as a characteristic biphasic pattern of c-Fos topology. NVC-deficient animals aberrantly adopted high-stress configurations under mild stress but regressed to low-stress templates during high-demand survival threats, thereby compromising defensive sustainability. Notably, the genetic NVC-enhancement model counteracted NVC impairments caused by chronic stress, thereby alleviating stress-driven emotional distress. These findings establish NVC in the BLA as an allostatic program that fine-tunes neural circuit activity during emotional responses, with implications for understanding and treating emotional disorders.

Animals

Glymphatic dysfunction mediates inflammation-driven vascular burden and cognitive decline in cerebral small vessel disease.

BACKGROUND: Cerebral small vessel disease (CSVD) is increasingly recognized as a disorder involving microvascular dysfunction, impaired perivascular clearance, and inflammatory processes. However, how systemic inflammatory burden, neurovascular coupling (NVC), glymphatic MRI markers, vascular lesion burden, and cognition are interrelated remains unclear. MATERIALS AND METHODS: In this prospective study, 155 patients with CSVD and 70 healthy controls (HCs) underwent multimodal MRI. NVC was quantified using the cerebral blood flow/fractional amplitude of low-frequency fluctuations ratio. Glymphatic function was assessed via the diffusion tensor image analysis along the perivascular space (ALPS) index, choroid plexus volume (CPV), and perivascular space (PVS) fractions. Structural equation modeling (SEM) was employed to evaluate the direct and indirect effects of inflammatory markers on vascular burden and cognitive performance. RESULTS: Patients with CSVD exhibited significantly diminished NVC (specifically in the right median cingulate and left frontal gyri) and impaired glymphatic function (lower ALPS-index; higher CPV and PVS fractions) compared to HCs. SEM revealed that inflammatory biomarkers exerted both a direct effect on vascular burden and a substantial indirect effect (accounting for 66.3% of the total effect) mediated through two pathways: a single-mediation path via glymphatic function (42.8%) and a serial-mediation path via NVC and glymphatic function (23.5%). Increased vascular burden was significantly associated with poorer cognitive performance. CONCLUSION: Inflammation drives CSVD progression and cognitive decline primarily through the disruption of NVC and glymphatic clearance mechanisms. These findings highlight glymphatic dysfunction as a critical mediator of inflammation-related structural brain damage.

Humans

Downregulation of Trpv4 and Klf2 in brain microvessels is associated with the progression of neurovascular dysfunction and cognitive impairment in a model of heart failure with preserved ejection fraction.

Vascular cognitive impairment (VCI) shares major risk factors with heart failure with preserved ejection fraction (HFpEF), including obesity, diabetes and hypertension. Yet VCI research often relies on single-stimulus models, whereas patients experience combined risk factors. We therefore assessed cerebrovascular and cognitive phenotypes in an HFpEF model and investigated underlying mechanisms. Male Lean and Obese ZSF1 rats underwent longitudinal assessments of blood pressure, glucose, cardiac function and behavioural performance. Cerebral blood flow and neurovascular coupling were assessed by laser speckle contrast imaging. White matter integrity, blood-brain barrier (BBB) permeability and vascular density were analyzed by (immuno)histochemistry. Cortical microvessels were isolated for transcriptomic profiling, and selected targets were validated using multiplex in-situ hybridization. Obese rats exhibited neurovascular uncoupling and impaired short- and long-term memory and spatial learning, accompanied by brain atrophy and reduced myelin. BBB permeability increased at 22-23 weeks and vascular density at 34-35 weeks in Obese versus Lean rats. Transcriptomic analysis of brain microvessels revealed altered processes related to angiogenesis, vasoreactivity, immune mechanisms and vascular remodelling, with consistent downregulation of Trpv4 and Klf2. Obese ZSF1 rats develop progressive neurovascular dysfunction associated with HFpEF onset and reduced Trpv4 and Klf2 expression in cerebral microvessels, two key vasoprotective genes.

Diastolic dysfunction

Osteochondroma of the atlas: a case report.

An extremely rare case of osteochondroma arising from the right lateral mass of an atlas was successfully treated by a complete removal through an oblique high cervical incision coupled with a transection of the underlying sternocleidomastoid muscle and careful freeing and retraction of the adjacent vital neurovascular structures.

Cervical Atlas

Surgical approaches to abnormalities of the nasal valve.

A systematic surgical approach to nasal valve abnormalities depends on adequate and precise exposure of the abnormality to be corrected and is facilitated by the use of magnification. Small anatomic disturbances in the region of the nasal valve can produce significant airway obstruction by narrowing the nasal valve angle. Normally, this angle between the caudal end of the upper lateral cartilage and the nasal septum is from 10 to 15 degree. In all patients with nasal airway obstruction, a meticulous clinical evaluation of the nasal valve is required. Nasal valve abnormalities can produce symptoms due to an already increased collapsibility of the nasal valve; therefore surgical intervention is directed toward reconstruction of normal anatomic relationships, usually by widening the nasal valve angle and preventing either extreme of rigidity or collapsibility. Appropriate and delicate handling of the intercartilaginous aponeurosis between the upper lateral (roof) cartilage and the lower lateral (lobular or alar) cartilage with prevention of excessive scar tissue formation usually can be achieved by dissection on the upper lateral cartilage. The surgical plane is beneath the overlying musculature and neurovascular layers. By preserving the mucocutaneous lining and by accurate suturing of incisions, primary wound healing is facilitated. Clinical experience suggest that the application of these concepts benefits patients by preventing or treating abnormalities of the nasal valve. Eventually, longterm results with preoperative and postoperative physiologic testing (rhinomanometry), coupled with critical clinical re-evaluation, should allow adoption, rejection, or, more likely, modification of the principles offered by this contribution.

Airway Obstruction

PCSK9 inhibition attenuates alcohol-induced cardiovascular dysfunction and links hepatic lipid accumulation to impaired myocardial contractile reserve.

Excessive alcohol consumption accelerates cardiovascular aging by promoting oxidative stress, inflammation, lipid dysregulation, fibrotic remodeling, and loss of ventricular-vascular reserve. PCSK9, a key regulator of cholesterol metabolism, has emerged as a mediator of age-related cardiovascular dysfunction and alcohol-associated liver and neurovascular injury. We investigated whether PCSK9 inhibition protects against alcohol-induced cardiovascular dysfunction and associated cardiac-hepatic injury in rats. Male Sprague-Dawley rats were assigned to pair-fed control or 35% ethanol liquid diet groups and treated weekly with subcutaneous alirocumab, 50 mg/kg, or vehicle for 6 weeks. Blood alcohol and cholesterol levels were measured; cardiac function was assessed by echocardiography and invasive pressure-volume analysis; and myocardial, vascular, and hepatic injury markers were quantified. Alirocumab reduced total cholesterol in both pair-fed and ethanol-fed rats without altering blood alcohol levels. Chronic ethanol exposure impaired systolic performance, myocardial contractile reserve, diastolic relaxation, and ventricular-arterial coupling, as reflected by reduced stroke volume, cardiac output, ejection fraction, fractional area change, dP/dtmax, stroke work, ESPVR slope, PRSW, and dP/dtmax-EDV, together with abnormalities in TauWeiss and dP/dtmin. PCSK9 inhibition markedly attenuated these functional deficits. Alirocumab also reduced ethanol-induced myocardial and vascular malondialdehyde accumulation and suppressed myocardial induction of NOX4, LOX1, iNOS, TNF-α, ANP, and profibrotic markers. Ethanol increased myocardial fibrosis, hepatic triglyceride accumulation, perilipin-2 staining, and mild hepatic fibrotic remodeling, all of which were attenuated by alirocumab. Liver triglyceride content correlated inversely with ESPVR slope and PRSW. These findings identify PCSK9 as a potential therapeutic target for alcohol-related cardiovascular dysfunction and associated cardiac-hepatic injury.

Accelerated aging