Objective Test the hypotheses that vitamin B12 deficiency would be prevalent in octogenarians and centenarians and associated with age, gender, race/ethnicity, living arrangements (community or skilled nursing facility), animal food intake, B-vitamin supplement use, atrophic gastritis, folate status, and hematological indicators. Design Population-based multi-ethnic sample of adults aged 80 to 89 and 98 and above. Setting Northern Georgia in the United States. Participants Men and women aged 80 to 89 (octogenarians, n = 80) and 98 and older (centenarians, n = 231). Measurements Wilcoxon signed-rank tests, Fisher℉s exact tests, and logistic regression analysis was used to examine the associations of vitamin B12 status with the variables of interest. Results After excluding participants receiving vitamin B12 injections (n = 17), the prevalence of vitamin B12 deficiency was higher in centenarians than in octogenarians (35.3% vs. 22.8%, p < 0.05, defined as plasma vitamin B12 < 258 pmol/L and serum methylmalonic acid > 271 nmol/L and methylmalonic acid > serum 2-methylcitrate) and in both age groups was correlated with significantly higher homocysteine (p < 0.05) and lower plasma and red cell folate (p < 0.01), but was not related to hemoglobin, anemia, mean cell volume, or macrocytosis. In logistic regression analysis, the probability of being vitamin B12-deficient was significantly increased by being a centenarian vs. octogenarian (p < 0.03), by being white vs. African American (p < 0.02), by increasing severity of atrophic gastritis (p < 0.001), and by not taking oral B-vitamin supplements (p < 0.01), but was not related to gender, living arrangements, or animal food intake. Conclusions Centenarians and octogenarians are at high risk for vitamin B12 deficiency for many of the same reasons identified in other older adult populations. Given the numerous potential adverse consequences of poor vitamin B12 status, efforts are needed to ensure vitamin B12 adequacy in these older adults.

Adipose tissue is both an energy storage depot and an endocrine organ. The impaired regulation of the secreted proteins of adipose tissue, known as adipocytokines, observed during obesity contributes to the onset of whole-body insulin resistance and the pathobiology of type 2 diabetes mellitus (T2DM). In addition, the global elevation of the intracellular glycosylation of proteins by O-linked β-N-acetylglucosamine (O-GlcNAc) via either genetic or pharmacological methods is sufficient to induce insulin resistance in both cultured cells and animal models. The elevation of global O-GlcNAc levels is associated with the altered expression of many adipocytokines. We have previously characterized the rodent adipocyte secretome during insulin sensitive and insulin resistant conditions. Here, we characterize and quantify the secretome and glycome of primary human adipocytes during insulin responsive and insulin resistant conditions generated by the classical method of hyperglycemia and hyperinsulinemia or by the pharmacological manipulation of O-GlcNAc levels. Using a proteomic approach, we identify 190 secreted proteins and report a total of 20 up-regulated and 6 down-regulated proteins that are detected in both insulin resistant conditions. Moreover, we apply glycomic techniques to examine (1) the sites of N-glycosylation on secreted proteins, (2) the structures of complex N- and O-glycans, and (3) the relative abundance of complex N- and O-glycans structures in insulin responsive and insulin resistant conditions. We identify 91 N-glycosylation sites derived from 51 secreted proteins, as well as 155 and 29 released N- and O-glycans respectively. We go on to quantify many of the N- and O-glycan structures between insulin responsive and insulin resistance conditions demonstrating no significant changes in complex glycosylation in the time frame for the induction of insulin resistance. Thus, our data support that the O-GlcNAc modification is involved in the regulation of adipocytokine secretion upon the induction of insulin resistance in human adipocytes.

The regulation of body weight/fat was studied by investigating mechanisms for compensatory adipose tissue growth after removal of bilateral epididymal fat pads from male adult Wistar rats. Food intake during the first 4 weeks and energy expenditure on Days 8-10 postsurgery were not different between lipectomized and sham operated rats. During Days 29–31 post surgery, a small (2.4%) but significant (P < 0.05) increase in heat production per metabolic body size was detected in lipectomized as compared with sham operated rats. The carcass composition of lipectomized and sham operated rats was not significantly different 16 weeks after surgery. The compensatory growth was fat pad–specific: mesenteric, retroperitoneal, and inguinal fat pads, but not perirenal fat pads, were heavier in lipectomized rats than in sham operated rats as early as 4 weeks postsurgery. Examination of fat cell size distribution in the compensating pads indicated a shift toward larger cells in retroperitoneal fat, but not in inguinal fat of lipectomized as compared with sham operated rats. Serum from lipectomized rats, but not media conditioned by exposure to retroperitoneal fat pads from lipectomized rats, stimulated proliferation of preadipocytes in vitro more than that from sham operated rats. Thus, compensatory adipose tissue growth after lipectomy may be mediated, in part, by blood-borne factors that are derived from tissues other than adipose tissue.

Anemia has been associated with increased physical and financial costs and occurs more frequently in older individuals. Therefore, the primary objectives of this study were to examine the prevalence and possible predictors of anemia in the very old. Hemoglobin was used to identify those with anemia in a group of centenarians and near centenarians (98+, n = 185) and octogenarians (n = 69), who were recruited as part of the population-based multidisciplinary Georgia Centenarian Study. Blood markers, including ferritin, vitamin B12, red blood cell folate, methylmalonic acid, creatinine, and C-reactive protein, demographic variables, and medication and/or supplement usage were used to determine possible predictors of anemia. The prevalence of anemia was 26.2% in octogenarians and 52.1% in centenarians. Low serum albumin (<3.6 g/dL) and decreased estimated glomerular filtration rate (<45 mL/min/m²) were predictors of anemia in centenarians. Anemia is a major health issue, particularly as people age. Because of the high prevalence of anemia in older individuals, awareness of the predictors associated with anemia becomes increasingly important so as to reduce the negative consequences associated with it and allow for the identification of steps that can be taken to correct anemia, including managing chronic disease.