Circulating sclerostin is increased in T2DM independently of gender and age. Serum sclerostin is also correlated with duration of T2DM, glycated hemoglobin, bone turnover markers, and BMD in T2DM patients. Additional studies are needed to evaluate the role of sclerostin on bone metabolism in this population.

Osteoporosis is a common chronic disease characterized by a decrease in bone mineral density, impaired bone strength, and an increased risk of fragility fractures. Fragility fractures are associated with significant morbidity, mortality and disability and are a major public health problem worldwide. The influence of nutritional factors on the development and progression of this disease can be significant and is not yet well established. Calcium intake and vitamin D status are considered to be essential for bone metabolism homeostasis. However, some recent studies have questioned the usefulness of calcium and vitamin D supplements in decreasing the risk of fractures. The adequate intake of protein, vegetables and other nutrients is also of interest, and recommendations have been established by expert consensus and clinical practice guidelines. It is important to understand the influence of nutrients not only in isolation but also in the context of a dietary pattern, which is a complex mixture of nutrients. In this review, we evaluate the available scientific evidence for the effects of the main dietary patterns on bone health. Although some dietary patterns seem to have beneficial effects, more studies are needed to fully elucidate the true influence of diet on bone fragility.

OBJECTIVEWnt/β-catenin signaling is related to the pathogenesis of several diseases. Sclerostin is an inhibitor of Wnt/β-catenin signaling. However, there are few data regarding the sclerostin levels and vascular disease. Our aim was to examine the relationship between serum sclerostin and atherosclerotic disease (AD) in type 2 diabetes mellitus (T2DM).RESEARCH DESIGN AND METHODSWe performed a cross-sectional study including 78 T2DM patients (45.3% females, mean age 59 ± 5.7 years; 54.7% males, 57.4 ± 6.7 years).RESULTSSerum sclerostin concentrations of T2DM patients in the AD group were significantly higher than in the non-AD group (P = 0.006). For each increase of 1 pmol/L in sclerostin level, there was a 4% increase of the risk of AD in T2DM patients. A concentration of ≥42.3 pmol/L showed a sensitivity of 69% and a specificity of 54.8% to detect an increased risk of AD. In males, sclerostin levels were higher in those with AD (P = 0.04), abnormal intima-media thickness (IMT) (P = 0.004), carotid plaques (P < 0.001), and aortic calcification (P < 0.001). In females, higher levels of sclerostin were related to abnormal IMT (P = 0.03) and aortic calcifications (P = 0.004). Homocysteine (β = 0.319 [95% CI 0.561–2.586], P = 0.003) and IMT (β = 0.330 [14.237–67.693], P = 0.003) were positively correlated with sclerostin.CONCLUSIONSCirculating sclerostin is increased in T2DM patients with atherosclerotic lesions. Although the sample size of our study was small, these data suggest that sclerostin levels could be a major modulator of Wnt signaling in AD with implications in T2DM patients.

The relationship between vitamin D status, calcium intake and the risk of developing type 2 diabetes (T2D) is a topic of growing interest. One of the most interesting non-skeletal functions of vitamin D is its potential role in glucose homeostasis. This possible association is related to the secretion of insulin by pancreatic beta cells, insulin resistance in different tissues and its influence on systemic inflammation. However, despite multiple observational studies and several meta-analyses that have shown a positive association between circulating 25-hydroxyvitamin D concentrations and the risk of T2D, no randomized clinical trials supplementing with different doses of vitamin D have confirmed this hypothesis definitively. An important question is the identification of what 25-hydroxyvitamin D levels are necessary to influence glycemic homeostasis and the risk of developing T2D. These values of vitamin D can be significantly higher than vitamin D levels required for bone health, but the currently available data do not allow us to answer this question adequately. Furthermore, a large number of observational studies show that dairy consumption is linked to a lower risk of T2D, but the components responsible for this relationship are not well established. Therefore, the importance of calcium intake in the risk of developing T2D has not yet been established. Although there is a biological plausibility linking the status of vitamin D and calcium intake with the risk of T2D, well-designed randomized clinical trials are necessary to answer this important question.

The present study was carried out to investigate the role of reactive oxygen species (ROS) metabolism in symptom development and pathogenesis in Nicotiana benthamiana plants upon infection with two strains of Pepper mild mottle virus, the Italian (PMMoV-I) and the Spanish (PMMoV-S) strains. In this host, it has been shown that PMMoV-I is less virulent and plants show the capability to recover 21 d after inoculation. Analyses of oxidative stress biomarkers, ROS-scavenging enzyme activities, and antioxidant compounds were conducted in plants at different post-infection times. Only PMMoV-I stimulated a defence response through: (i) up-regulation of different superoxide dismutase isozymes; (ii) maintenance of adequate levels of three peroxiredoxins (2-Cys Prx, Prx IIC, and Prx IIF); and (iii) adjustments in the glutathione pool to maintain the total glutathione content. Moreover, there was an increase in the level of oxidized glutathione and ascorbate in the recovery phase of PMMoV-I-infected plants. The antioxidant response and the extent of oxidative stress in N. benthamiana plants correlates to: (i) the severity of the symptoms elicited by either strain of PMMoV; and (ii) the high capacity of PMMoV-I-infected plants for symptom recovery and delayed senescence, compared with PMMoV-S-infected plants.

Hypophosphatasia (HPP) is a rare genetic disease characterized by a decrease in the activity of tissue non-specific alkaline phosphatase (TNSALP). TNSALP is encoded by the ALPL gene, which is abundantly expressed in the skeleton, liver, kidney, and developing teeth. HPP exhibits high clinical variability largely due to the high allelic heterogeneity of the ALPL gene. HPP is characterized by multisystemic complications, although the most common clinical manifestations are those that occur in the skeleton, muscles, and teeth. These complications are mainly due to the accumulation of inorganic pyrophosphate (PPi) and pyridoxal-5′-phosphate (PLP). It has been observed that the prevalence of mild forms of the disease is more than 40 times the prevalence of severe forms. Patients with HPP present at least one mutation in the ALPL gene. However, it is known that there are other causes that lead to decreased alkaline phosphatase (ALP) levels without mutations in the ALPL gene. Although the phenotype can be correlated with the genotype in HPP, the prediction of the phenotype from the genotype cannot be made with complete certainty. The availability of a specific enzyme replacement therapy for HPP undoubtedly represents an advance in therapeutic strategy, especially in severe forms of the disease in pediatric patients.

Recent evidence has revealed anti-inflammatory properties of vitamin D as well as extra-skeletal activity. In this context, vitamin D seems to be involved in infections, autoimmune diseases, cardiometabolic diseases, and cancer development. In recent years, the relationship between vitamin D and insulin resistance has been a topic of growing interest. Low 25-hydroxyvitamin D (25(OH)D) levels appear to be associated with most of the insulin resistance disorders described to date. In fact, vitamin D deficiency may be one of the factors accelerating the development of insulin resistance. Vitamin D deficiency is a common problem in the population and may be associated with the pathogenesis of diseases related to insulin resistance, such as obesity, diabetes, metabolic syndrome (MS) and polycystic ovary syndrome (PCOS). An important question is the identification of 25(OH)D levels capable of generating an effect on insulin resistance, glucose metabolism and to decrease the risk of developing insulin resistance related disorders. The benefits of 25(OH)D supplementation/repletion on bone health are well known, and although there is a biological plausibility linking the status of vitamin D and insulin resistance supported by basic and clinical research findings, well-designed randomized clinical trials as well as basic research are necessary to know the molecular pathways involved in this association.

Cardiovascular diseases are a health problem throughout the world, especially in people with diabetes. The identification of cardiovascular disease biomarkers can improve risk stratification. Sclerostin is a modulator of the Wnt/β-catenin signalling pathway in different tissues, and it has recently been linked to vascular biology. The current study aimed to evaluate the relationship between circulating sclerostin levels and cardiovascular and non-cardiovascular mortality in individuals with and without type 2 diabetes. We followed up a cohort of 130 participants (mean age 56.8 years; 48.5% females; 75 with type 2 diabetes; 46 with prevalent cardiovascular disease) in which serum sclerostin levels were measured at the baseline. Time to death (both of cardiovascular and non-cardiovascular causes) was assessed to establish the relationship between sclerostin and mortality. We found that serum sclerostin concentrations were significantly higher in patients with prevalent cardiovascular disease (p<0.001), and independently associated with cardiovascular mortality (p = 0.008), showing sclerostin to be a stronger predictor of mortality than other classical risk factors (area under the curve = 0.849 vs 0.823). The survival analysis showed that an increase of 10 pmol/L in the serum sclerostin level resulted in a 31% increase in cardiovascular mortality. However, no significant association was observed between sclerostin levels and non-cardiovascular mortality (p = 0.346).From these results, we conclude that high sclerostin levels are related to mortality due to cardiovascular causes. The clinical implication of these findings is based on the possible use of serum sclerostin as a new biomarker of cardiovascular mortality risk in order to establish preventive strategies.