Irritant-evoked reflex tachyarrhythmia in spontaneously hypertensive rats is reduced by inhalation of TRPM8 agonists l-menthol and WS-12

Acute and Persistent Cardiovascular Effects of Menthol E-Cigarettes in Mice

BACKGROUND

Although e-cigarettes provide an alternative to conventional smoking, the cardiovascular impacts of e-cigarette use are unresolved. The popularity of menthol e-cigarettes has surged recently and may escalate further with bans on combustible menthol cigarettes and e-cigarette flavors other than menthol and tobacco. Despite recent evidence in mice that menthol e-cigarettes acutely induce cardiac arrhythmias, the impacts of repeated menthol e-cigarette use on cardiovascular function and the cardiac proteome remain unclear. We therefore investigated the acute and persistent cardiovascular effects of menthol e-cigarettes in a mouse model.

METHODS AND RESULTS

Adult C57BL/6J mice with ECG and blood pressure radiotransmitters were exposed to e-cigarette aerosols (180-270 puffs/day; n=4-8/group). One-day exposures to nicotine-containing e-cigarette aerosols depressed heart rate variability regardless of flavor, but menthol e-cigarette aerosols uniquely increased heart rate and urine epinephrine and elicited spontaneous ventricular premature beats. Menthol e-cigarette aerosols consistently increased blood pressure acutely, and this effect recurred throughout the 20-day regimen. Pretreatment with atenolol abolished e-cigarette-induced arrhythmias, suggesting the involvement of β1-adrenoceptors. After 4 weeks of exposure to JUUL Menthol aerosol, mice had basal sinus bradycardia that persisted up to 3 weeks after exposure cessation. After cessation, e-cigarette-exposed mice also exhibited an altered chronotropic response to restraint stress and prolonged ventricular repolarization (corrected QT interval). Integrated proteomic and phosphoproteomic analysis of cardiac tissue harvested from mice exposed to menthol e-cigarette aerosols for 5 and 20 days revealed molecular signatures of dilated and arrhythmogenic cardiomyopathy.

CONCLUSIONS

Exposure to menthol e-cigarette aerosols induces persistent cardiovascular autonomic imbalance in vivo. These findings raise the possibility of similar effects in humans using mentholated e-cigarettes.

Genetic and immune identification and functional analysis of TRPM8 as a potential biomarker for pancreatic adenocarcinoma proliferation

BACKGROUND

Pancreatic adenocarcinoma (PAAD), a member of highly lethal malignant tumors, has a poor outcome and extremely poor prognosis. The transient receptor potential (TRP) superfamily, a group of nonselective cation channels, is capable of influencing cellular functions by regulating calcium homeostasis. In addition, it has been shown that TRP channels can also affect various cellular phenotypes by regulating gene transcription levels and are involved in the development of a variety of malignant tumors.

AIMS

In order to find new therapeutic targets and biomarkers to improve the clinical prognosis of pancreatic cancer, we performed genetic and immunological characterization of TRP channels in PAAD, as well as related functional and prognostic analyses.

METHODS AND RESULTS

We investigated the expression, genetic alterations, methylation levels, and immune infiltration levels of TRP channels in PAAD, and further also analyzed the function of TRP channels in PAAD and their prognostic value for PAAD patients. Our results suggest that TRPM8 may contribute to tumor proliferation by controlling the PI3K-AKT-mTOR signaling pathway in PAAD.

CONCLUSION

After careful evaluation of the accumulated data, we concluded that TRPM8 has potential as a prognostic indicator and prospective therapeutic target in PAAD.

Disruption of Atrial Rhythmicity by the Air Pollutant 1,2-Naphthoquinone: Role of Beta-Adrenergic and Sensory Receptors

The combustion of fossil fuels contributes to air pollution (AP), which was linked to about 8.79 million global deaths in 2018, mainly due to respiratory and cardiovascular-related effects. Among these, particulate air pollution (PM2.5) stands out as a major risk factor for heart health, especially during vulnerable phases. Our prior study showed that premature exposure to 1,2-naphthoquinone (1,2-NQ), a chemical found in diesel exhaust particles (DEP), exacerbated asthma in adulthood. Moreover, increased concentration of 1,2-NQ contributed to airway inflammation triggered by PM2.5, employing neurogenic pathways related to the up-regulation of transient receptor potential vanilloid 1 (TRPV1). However, the potential impact of early-life exposure to 1,2-naphthoquinone (1,2-NQ) on atrial fibrillation (AF) has not yet been investigated. This study aims to investigate how inhaling 1,2-NQ in early life affects the autonomic adrenergic system and the role played by TRPV1 in these heart disturbances. C57Bl/6 neonate male mice were exposed to 1,2-NQ (100 nM) or its vehicle at 6, 8, and 10 days of life. Early exposure to 1,2-NQ impairs adrenergic responses in the right atria without markedly affecting cholinergic responses. ECG analysis revealed altered rhythmicity in young mice, suggesting increased sympathetic nervous system activity. Furthermore, 1,2-NQ affected β1-adrenergic receptor agonist-mediated positive chronotropism, which was prevented by metoprolol, a β1 receptor blocker. Capsazepine, a TRPV1 blocker but not a TRPC5 blocker, reversed 1,2-NQ-induced cardiac changes. In conclusion, neonate mice exposure to AP 1,2-NQ results in an elevated risk of developing cardiac adrenergic dysfunction, potentially leading to atrial arrhythmia at a young age.