Multiple Micronutrients,Including Zinc,Selenium and Iron,Are Positively Associated with Anemia in New Zealand Aged Care Residents

Anemia is a significant comorbidity for older adults not fully attributable to iron deficiency. Low-grade inflammation and other micronutrient deficiencies also contribute. This cross-sectional study examined the relationships between nutrient and non-nutrient factors with hemoglobin and anemia in 285 residents (>65 years) of 16 New Zealand aged-care facilities. Blood samples were analyzed for hemoglobin, ferritin, sTfR, hepcidin, zinc, selenium, and interleukin-6 (IL-6), (with ferritin, sTfR, zinc and selenium adjusted for inflammation). Linear regression models examined the relationships between micronutrient biomarkers (iron, zinc, selenium, vitamin B-12 and D), age, sex, and health factors with hemoglobin. Thirty-two percent of participants exhibited anemia, although <2% had either depleted iron stores or iron deficiency. Plasma zinc and selenium deficiencies were present in 72% and 38% of participants, respectively. Plasma zinc and total body iron (TBI) were positively associated (p < 0.05) with hemoglobin, while gastric acid suppressing medications, hepcidin, and interleukin-6 were inversely associated. These relationships were maintained after the application of anemia cut-offs. These findings emphasize the importance of considering multiple micronutrient deficiencies as risk factors for anemia.     

Gain-of-Function Lrp5 Mutation Improves Bone Mass and Strength and Delays Hyperglycemia in a Mouse Model of Insulin-Deficient Diabetes

High fracture rate and high circulating levels of the Wnt inhibitor, sclerostin, have been reported in diabetic patients. We studied the effects of Wnt signaling activation on bone health in a mouse model of insulin-deficient diabetes. We introduced the sclerostin-resistant Lrp5^A214V mutation, associated with high bone mass, in mice carrying the Ins2^Akita mutation (Akita), which results in loss of beta cells, insulin deficiency, and diabetes in males. Akita mice accrue less trabecular bone mass with age relative to wild type (WT). Double heterozygous Lrp5^A214V/Akita mutants have high trabecular bone mass and cortical thickness relative to WT animals, as do Lrp5^A214V single mutants. Likewise, the Lrp5^A214V mutation prevents deterioration of biomechanical properties occurring in Akita mice. Notably, Lrp5^A214V/Akita mice develop fasting hyperglycemia and glucose intolerance with a delay relative to Akita mice (7 to 8 vs. 5 to 6 weeks, respectively), despite lack of insulin production in both groups by 6 weeks of age. Although insulin sensitivity is partially preserved in double heterozygous Lrp5^A214V/Akita relative to Akita mutants up to 30 weeks of age, insulin-dependent phosphorylated protein kinase B (pAKT) activation in vitro is not altered by the Lrp5^A214V mutation. Although white adipose tissue depots are equally reduced in both compound and Akita mice, the Lrp5^A214V mutation prevents brown adipose tissue whitening that occurs in Akita mice. Thus, hyperactivation of Lrp5-dependent signaling fully protects bone mass and strength in prolonged hyperglycemia and improves peripheral glucose metabolism in an insulin independent manner. Wnt signaling activation represents an ideal therapeutic approach for diabetic patients at high risk of fracture. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).     

Failure of clonidine treatment in benzodiazepine withdrawal

Six subjects, dependent on benzodiazepines for at least 2 years, were gradually withdrawn, using placebo substitution, while taking clonidine. After withdrawal was complete, subjects were switched to clonidine-placebo. Despite administration of clonidine at doses sufficient to produce a fall in blood pressure, an abstinence syndrome was seen in five of the subjects. In none of these cases was the withdrawal syndrome exacerbated by changing from clonidine to clonidine-placebo. Scores of depression, subjective anxiety, observed anxiety and somatic symptoms did not change throughout the study.     

Chemokine production by human vascular smooth muscle cells: modulation by IL-13

1. The production of chemokines by vascular smooth muscle cells (SMC) is implicated in the pathogenesis of atherosclerosis, although the factors regulating chemokine production by these cells are incompletely characterized.
2. We describe the differential stimulation of interleukin-(IL)-8, monocyte chemoattractant protein (MCP)-1 and regulated on activation normal T-cell expressed and secreted (RANTES) synthesis following treatment of human vascular SMC with IL-1α or tumour necrosis factor α (TNFα). Under basal conditions, cultured SMC release very low amounts of IL-8, MCP-1 and RANTES as assessed by specific ELISA. Concentration-response studies with IL-1α or TNFα revealed that each stimulus induced a similar amount of MCP-1. In contrast approximately three fold more IL-8 was induced by IL-1α than by TNFα whereas significant RANTES production was induced only by TNFα. These findings point to a divergence in the regulation of synthesis of the different chemokines in response to IL-1α or TNFα stimulation.
3. The T-cell derived cytokines IL-10 and IL-13 were also found to have differential effects on chemokine production by SMC. IL-13, but not IL-10, significantly enhanced IL-8 and MCP-1 release in response to IL-1α or TNFα. This increase in chemokine release appeared to be accounted for by increased mRNA expression.
4. These findings provide support for the concept that smooth muscle cells can have an active role in a local immune response via the production of chemokines which can be selectively modulated by T-cell derived cytokines.