Forkhead box O3 longevity genotype may attenuate the impact of hypertension on risk of intracerebral haemorrhage

Exploring the Relationship of rs2802292 with Diabetes and NAFLD in a Southern Italian Cohort-Nutrihep Study

Background: The minor G-allele of FOXO3 rs2802292 is associated with human longevity. The aim of this study was to test the protective effect of the variant against the association with type 2 Diabetes and NAFLD. Methods: rs2802292 was genotyped in a large population of middle-aged subjects (n = 650) from a small city in Southern Italy. All participants were interviewed to collect information about lifestyle and dietary habits; clinical characteristics were recorded, and blood samples were collected from all subjects. The association between rs2802292 and NAFLD or diabetes was tested using a logistic model and mediation analysis adjusted for covariates. Results: Overall, the results indicated a statistical association between diabetes and rs2802292, especially for the TT genotype (OR = 2.14, 1.01 to 4.53 95% C.I., p = 0.05) or in any case for those who possess the G-allele (OR = 0.45, 0.25 to 0.81 95% C.I., p = 0.008). Furthermore, we found a mediation effect of rs2802292 on diabetes (as mediator) and NAFLD. There is no direct relationship between rs2802292 and NAFLD, but the effect is direct (β = 0.10, -0.003 to 0.12 95% C.I., p = 0.04) on diabetes, but only in TT genotypes. Conclusions: The data on our cohort indicate that the longevity-associated FOXO3 variant may have protective effects against diabetes and NAFLD.

Vascular smooth muscle cell-specific Igf1r deficiency exacerbates the development of hypertension-induced cerebral microhemorrhages and gait defects

Cerebrovascular fragility and cerebral microhemorrhages (CMH) contribute to age-related cognitive impairment, mobility defects, and vascular cognitive impairment and dementia, impairing healthspan and reducing quality of life in the elderly. Insulin-like growth factor 1 (IGF-1) is a key vasoprotective growth factor that is reduced during aging. Circulating IGF-1 deficiency leads to the development of CMH and other signs of cerebrovascular dysfunction. Here our goal was to understand the contribution of IGF-1 signaling on vascular smooth muscle cells (VSMCs) to the development of CMH and associated gait defects. We used an inducible VSMC-specific promoter and an IGF-1 receptor (Igf1r) floxed mouse line (Myh11-CreERT2 Igf1rf/f) to knockdown Igf1r. Angiotensin II in combination with L-NAME-induced hypertension was used to elicit CMH. We observed that VSMC-specific Igf1r knockdown mice had accelerated development of CMH, and subsequent associated gait irregularities. These phenotypes were accompanied by upregulation of a cluster of pro-inflammatory genes associated with VSMC maladaptation. Collectively our findings support an essential role for VSMCs as a target for the vasoprotective effects of IGF-1, and suggest that VSMC dysfunction in aging may contribute to the development of CMH.

FOXO3 longevity genotype attenuates the impact of hypertension on cerebral microinfarct risk

OBJECTIVE

The G -allele of FOXO3 SNP rs2802292 , which is associated with human resilience and longevity, has been shown to attenuate the impact of hypertension on the risk of intracerebral hemorrhage (ICH). We sought to determine whether the FOXO3 G -allele similarly attenuates the impact of hypertension on the risk of cerebral microinfarcts (CMI).

METHODS

From a prospective population-based cohort of American men of Japanese ancestry from the Kuakini Honolulu Heart Program (KHHP) and Kuakini Honolulu-Asia Aging Study (KHAAS) that had brain autopsy data, age-adjusted prevalence of any CMI on brain autopsy was assessed. Logistic regression models, adjusted for age at death, cardiovascular risk factors, FOXO3 and APOE-ε4 genotypes, were utilized to determine the predictors of any CMI. Interaction of FOXO3 genotype and hypertension was analyzed.

RESULTS

Among 809 men with complete data, 511 (63.2%) participants had evidence of CMI. A full multivariable model demonstrated that BMI [odds ratio (OR) 1.07, 95% confidence interval (CI) 1.01-1.14, P  = 0.015) was the only predictor of CMI, while hypertension was a borderline predictor (OR 1.44, 95% CI 1.00-2.08, P  = 0.052). However, a significant interaction between FOXO3 G -allele carriage and hypertension was observed ( P  = 0.020). In the stratified analyses, among the participants without the longevity-associated FOXO3 G -allele, hypertension was a strong predictor of CMI (OR 2.25, 95% CI 1.34-3.77, P  = 0.002), while among those with the longevity-associated FOXO3 G -allele, hypertension was not a predictor of CMI (OR 0.88, 95% CI 0.51-1.54, P  = 0.66).

CONCLUSION

The longevity-associated FOXO3 G -allele mitigates the impact of hypertension on the risk of CMI.