Objective-To study matrix metalloproteinase 2 (MMP-2) effects on transforming growth factor-␤1 (TGF-␤1) activation status and downstream signaling during arterial aging. Methods and Results-Western blotting and immunostaining showed that latent and activated TGF-␤1 are markedly increased within the aorta of aged Fisher 344 cross-bred Brown Norway (30 months of age) rats compared with adult (8 months of age) rats. Aortic TGF-␤1-type II receptor (T␤RII), its downstream molecules p-similar to mad-mother against decapentaplegic (SMAD)2/3 and SMAD4, fibronectin, and collagen also increased with age. Moreover, TGF-␤1 staining is colocalized with that of activated MMP-2 within the aged arterial wall and vascular smooth muscle cell (VSMC) in vitro, and this physical association was confirmed by coimmunoprecipitation. Incubation of young aortic rings ex vivo or VSMCs in vitro with activated MMP-2 enhanced active TGF-␤1, collagen, and fibronectin expression to the level of untreated old counterparts, and this effect was abolished via inhibitors of MMP-2. Interestingly, in old untreated rings or VSMCs, the increased TGF-␤1, fibronectin, and collagen were also substantially reduced by inhibition of MMP-2. Conclusions-Active TGF-␤1, its receptor, and receptor-mediated signaling increase within the aortic wall with aging.TGF-␤1 activation is dependent, in part at least, by a concomitant age-associated increase in MMP-2 activity. Thus, MMP-2-activated TGF-␤1, and subsequently T␤RII signaling, is a novel molecular mechanism for arterial aging.

Increased angiotensin II (Ang II), matrix metalloproteinase type II (MMP2), and sympathetic activity accompany age-associated arterial remodeling. To analyze this relationship, we infused a low subpressor dose of Ang II into young (8 months old) rats. This increased carotid arterial MMP2 transcription, translation, and activation, as well as transforming growth factor-␤1 activity and collagen deposition. A higher Ang II concentration, which increased arterial pressure to that of old (30 months old) untreated rats, produced carotid media thickening and intima infiltration by vascular smooth muscle cells (VSMCs). Ex vivo, Ang II increased MMP2 activity in carotid rings from young rats to that of untreated old rats. Ang II also increased the ability of early passage VSMCs from young rats to invade a synthetic basement membrane, similar to that of untreated VSMCs from old rats. The MMP inhibitor GM6001 and the AT 1 receptor antagonist Losartan inhibited these effects. The ␣-adrenoreceptor agonist phenylephrine increased arterial Ang II protein, causing MMP2 activation and intima and media thickening. Exposure of young VSMCs to phenylephrine in vitro increased Ang II protein and MMP2 activity to the levels of old VSMCs; Losartan abolished these effects. Thus, Ang II-induced effects on MMP2, transforming growth factor-␤1, collagen, and VSMCs are central to the arterial remodeling that accompanies advancing age. (Am J Pathol 2005,

Among post-menopausal women, a higher testosterone/estradiol ratio was associated with an elevated risk for incident CVD, CHD, and HF events, higher levels of testosterone associated with increased CVD and CHD, whereas higher estradiol levels were associated with a lower CHD risk. Sex hormone levels after menopause are associated with women's increased CVD risk later in life.

MHO participants had a higher prevalence of subclinical coronary atherosclerosis than metabolically-healthy normal-weight participants, which supports the idea that MHO is not a harmless condition. This association, however, was mediated by metabolic risk factors at levels below those considered abnormal, which suggests that the label of metabolically healthy for obese subjects may be an artifact of the cutoff levels used in the definition of metabolic health.