Vitamin D Role and Use in Prediabetes

ObjectiveTo review the role of vitamin D in prediabetes on the basis of evidence from human studies.MethodsEnglish-language literature in MEDLINE (January 1969-July 2009) was searched for observational studies and randomized controlled trials of vitamin D deficiency and treatment in prediabetes, including impaired fasting glucose, impaired glucose tolerance, and metabolic syndrome. Search terms included hyperglycemia, glucose, glycohemoglobin, insulin resistance, diabetes, homeostasis model assessment, insulin secretion, vitamin D, and related terms. Publications were also identified from review articles and references in the found articles. Abstracts, conference proceedings, case reports, and letters were excluded. Articles concerning only type 1 and type 2 diabetes, hemodialysis, or hyperparathyroidism and studies in children were also excluded.ResultsVitamin D insufficiency is defined by a circulating 25-hydroxyvitamin D concentration less than 30 ng/mL, and it is prevalent in the United States (77% of the population). Most cross-sectional and prospective studies in various populations show inverse association between circulating 25-hydroxyvitamin D and fasting plasma glucose, impaired glucose tolerance, hemoglobin A_1c, metabolic syndrome, and incidence of prediabetes. A few clinical trials suggest beneficial effect of vitamin D supplementation in prediabetes, including improved insulin secretion, basal fasting insulin sensitivity, and postprandial peripheral insulin resistance. The limitations of the studies are small sample size, short duration of follow-up, lack of control groups, and inability to achieve vitamin D sufficiency with treatment.ConclusionAvailable data suggest that achieving vitamin D sufficiency may be beneficial in patients with prediabetes, although clinical trials are needed to provide evidence-based recommendations. (Endocr Pract. 2010;16:476-485)     

Evaluation of Vitamin D Repletion Regimens to Correct Vitamin D Status in Adults

ObjectiveTo determine the efficacy and safety of commonly prescribed regimens for the treatment of vitamin D insufficiency.MethodsWe performed a retrospective analysis of 306 consecutive patients who were prescribed ergocalciferol (vitamin D₂) for correction of vitamin D insufficiency at the Atlanta Veterans Affairs Medical Center between February 2003 and May 2006. Serum levels of parathyroid hormone, 25-hydroxyvitamin D (25-OHD), and calcium were compared before and after treatment with ergocalciferol. Patients who did not have a 25-OHD determination (n = 41) were excluded from analysis. Vitamin D deficiency, insufficiency, and sufficiency were defined as a serum 25-OHD level of < 20 ng/mL, 21 to 29 ng/mL, and > 30 ng/mL, respectively.ResultsWe identified 36 discrete prescribing regimens. The 3 most common regimens were ergocalciferol 50,000 IU once weekly for 4 weeks followed by 50,000 IU once monthly for 5 months (n = 48); ergocalciferol 50,000 IU once monthly for 6 months (n = 80); and ergocalciferol 50,000 IU 3 times weekly for 6 weeks (n = 27). Each of these 3 treatments significantly increased serum 25-OHD (P < .01), but vitamin D sufficiency was achieved in only 38%, 42%, and 82% of study subjects, respectively. Regimens with > 600,000 IU of ergocalciferol given for a mean of 60 ± 40 days achieved sufficiency in 64% of cases, without vitamin D toxicity.ConclusionIn this study, regimens that contained at least 600,000 IU of ergocalciferol appeared to be the most effective in achieving vitamin D sufficiency. Guidelines for the treatment of vitamin D insufficiency in healthy adults should be developed. (Endocr Pract. 2009;15:95-103)     

Tibial Tenderness Identifies Secondary Hyperparathyroidism Responding to High-Dose Vitamin D in Pakistani Women

ObjectiveTo assess the utility of anterior tibial tenderness (ATT) measured by visual analogue scoring (VAS) as a clinical diagnostic tool for vitamin D deficiency in a high-risk population of Pakistani women.MethodsATT was measured by VAS in 75 premenopausal women age 17 to 56 years (mean, 41.3 years) with generalized aches and pains and calcium <11 mg/dL (normal, 8 to 11 mg/dL) who were seen at a tertiary care center in Lahore, Pakistan. This was followed by administration of 1.8 million units of vitamin D3 in divided doses. ATT, vitamin D, and parathyroid hormone (PTH) levels were checked before and after the injections. Correlation between ATT, vitamin D, and PTH, as well as changes in ATT, vitamin D, and PTH following supplementation were determined.ResultsPre-intervention average calcium and vitamin D were 9.3 mg/dL (range, 8 to 10.3 mg/dL) and 12.1 ng/mL (range, 1.5 to 32.6 ng/mL), respectively. Seventy-four percent of the participants (53/75) had vitamin D deficiency and elevated PTH (>60 pg/mL). Mean PTH was 81.6 pg/mL (range, 29.1 to 370 pg/mL). Changes in ATT correlated strongly (r = 0.422; P = .013) with changes in PTH. Following supplementation, there was significant improvement in ATT (P<.01) and vitamin D level (P<.01), with a decrease in PTH level (P<.01).ConclusionATT is a valid clinical diagnostic measure of vitamin D deficiency in South Asian women. (Endocr Pract. 2013;19:596-601)     

Comparison of Vitamin D Replacement Strategies with High-Dose Intramuscular or Oral Cholecalciferol: A Prospective Intervention Study

Objective: To ascertain the frequency of correction of vitamin D deficiency (VDD) with single or multiple doses of oral (PO) and intramuscular (IM) administration of 2 high-dose preparations of vitamin D₃ (VD₃).Methods: This was a prospective intervention study conducted in an ambulatory care setting. One hundred participants with VDD (25-hydroxy vitamin D &lsqb;25-OHD] <20 ng/mL) were randomized to receive a dose of 600,000 or 200,000 IU of VD₃ via a PO or IM route. The main outcome measure was serum 25-OHD levels at 2, 4, and 6 months after the intervention.The same dose was repeated in participants if 25-OHD remained <30 ng/mL at 2 and 4 months.Results: At 2 months, VDD was corrected in 93.8% of participants in Group 1 (600,000 IU IM); 83.3% in Group 2 (600,000 IU PO), 87.5% in Group 3 (200,000 IU IM), and 70.6% in Group 4 (200,000 IU PO). The mean changes from baseline in vitamin D levels at 2 months were 29.6 ± 13.7, 19.8 ± 12.3, 18.3 ± 10.6, and 13.7 ± 7.8 ng/mL in Groups 1, 2, 3, and 4, respectively. The mean levels remained significantly higher from baseline in all groups at all time points during the 6 months of observation. The mean 25-OHD level achieved in Group 1 was significantly higher than all other groups at 6 months.Conclusion: Two months after the intervention, VDD was corrected in more than 70% of participants with a single dose of either 600,000 or 200,000 IU given PO or IM.Abbreviations: ALT = alanine transaminase IM = intramuscular iPTH = intact parathyroid hormone IQR = interquartile range 25-OHD = 25 hydroxyvitamin D PO = oral VD₃ = vitamin D3 (cholecalciferol) VDD = vitamin D deficiency VDI = vitamin D insufficiency     

Vitamin D Receptor Gene Polymorphisms and Prognosis of Breast Cancer among African-American and Hispanic Women

Background

Vitamin D plays a role in cancer development and acts through the vitamin D receptor (VDR). Although African-Americans have the lowest levels of serum vitamin D, there is a dearth of information on VDR gene polymorphisms and breast cancer among African-Americans and Hispanics. This study examines whether VDR gene polymorphisms are associated with breast cancer in these cohorts.

Methods

Blood was collected from 232 breast cancer patients (Cases) and 349 non-cancer subjects (Controls). Genotyping for four polymorphic variants of VDR (FokI, BsmI, TaqI and ApaI) was performed using the PCR-RFLP method.

Results

An increased association of the VDR-Fok1 f allele with breast cancer was observed in African-Americans (OR = 1.9, p = 0.07). Furthermore, the FbTA, FbtA and fbtA haplotypes were associated with breast cancer among African-Americans (p<0.05). Latinas were more likely to have the VDR-ApaI alleles (Aa or aa) (p = 0.008). The VDR-ApaI aa genotype was significantly associated with poorly-differentiated breast tumors (p = 0.04) in combined Cases. Kaplan-Meier survival analysis showed decreased 5-year disease-free-survival (DFS) in breast cancer patients who had the VDR-Fok1 FF genotype (p<0.05). The Cox regression with multivariate analysis revealed the independent predictor value of the VDR-FokI polymorphism for DFS. The other three variants of VDR (BsmI, TaqI and ApaI) were not associated with disease outcome.

Conclusions

VDR haplotypes are associated with breast cancer in African-Americans, but not in Hispanic/Latinas. The VDR-FokI FF genotype is linked with poor prognosis in African-American women with breast cancer.     

Vitamin D and Prebiotics may benefit The Intestinal Microbacteria and improve Glucose Homeostasis in Prediabetes and Type 2 Diabetes

ObjectiveTo review the role of human large bowel microbacteria (microbiota) in the glucose homeostasis, to address vitamin D (VD) and prebiotics interactions with microbiota, and to summarize recent randomized clinical trials (RCTs) of VD and prebiotics supplementation in prediabetes (PreDM) and type 2 diabetes mellitus (T2DM).MethodsPrimary literature was reviewed in the following areas: composition and activity of human microbiota associated with PreDM and T2DM, interactions between microbiota and glucose homeostasis, the interaction of microbiota with VD/prebiotics, and RCTs of VD/prebiotics in subjects with PreDM or T2DM.ResultsThe human microbiota is comprised of 100 trillion bacteria with an aggregate genome that is 150-fold larger than the human genome. Data from the animal models and human studies reveal that an “obesogenic” diet results into the initial event of microbiota transformation from symbiosis to dysbiosis. The microbial antigens, such as Gram(-) bacteria and lipopolysaccharide (LPS), translocate to the host interior and trigger increased energy harvesting and Toll-like receptor (TLR) activation with subsequent inflammatory pathways signaling. The “double hit” of steatosis (ectopic fat accumulation) and “—itis” (inflammation) and contribution of “corisks” (e.g., vitamin D deficiency [VDD]) are required to activate molecular signaling, including impaired insulin signaling and secretion, that ends with T2DM and associated diseases. Dietary changes (e.g., prebiotics, VD supplementation) may ameliorate this process if initiated prior to the process becoming irreversible.ConclusionEmerging evidence suggests an important role of microbiota in glucose homeostasis. VD supplementation and prebiotics may be useful in managing PreDM and T2DM. (Endocr Pract. 2013;19:497-510)     

The Importance of Vitamin D Level in Subacute Thyroiditis Disease and the Effect of Vitamin D on Disease Prognosis

Objective: Subacute thyroiditis (SAT) is an inflammatory thyroid disease that manifests with severe pain. The presence of the vitamin D receptor in immune system cells shows that vitamin D deficiency can trigger inflammatory diseases. The aim of the present study was to determine the prevalence of vitamin D deficiency in SAT patients, and the relationship between vitamin D level and permanent hypothyroidism and recurrence rate.Methods: In this retrospective study, 25-hydroxyvitamin D (25&lsqb;OH]D) levels of 170 SAT patients and 86 control subjects were compared.Results: The 25(OH)D levels were significantly lower in the SAT patients, and there was no seasonal difference. A negative correlation was determined between the erythrocyte sedimentation rate and 25(OH)D, but no significant relationship was found between vitamin D level and prognosis.Conclusion: As a result of this study, it was shown that vitamin D levels in subacute thyroiditis patients were significantly lower than in the healthy control group. Although there is no relationship between vitamin D level and disease prognosis, vitamin D deficiency may increase the rate of respiratory tract infections (especially, influenza, coxsackievirus, measles, adenovirus, retroviruses) and eventually SAT development.     

胃癌合并糖尿病患者术后强化血糖控制的疗效分析

目的：探讨胃癌合并糖尿病患者术后强化血糖控制的临床疗效及其对预后的影响。方法：根据不同血糖控制方法,将96例胃癌合并糖尿病术后患者分为强化血糖控制组50例（血糖控制在4.4-6.1mol/L）和对照组46例（血糖控制在6.1~11.1mol/L）。监测患者术后1、3、7天的空腹血糖（FBG）、空腹胰岛素定量（FINS）、及C反应蛋白（CRP）水平,并计算胰岛素抵抗指数（HOMA-IR）,比较分析两组术后恢复情况及并发症发生情况。结果：术后1、3、7天,强化血糖控制组FBG、lnHOMA-IR及CRP水平均显著低于对照组,差异有统计学意义（P〈0.05）;术后1天两组间FINS水平差异无统计学意义（P〉0.05）,而术后3、7天,二者之间差异有统计学意义（P〈0.05）;强化血糖控制组术后发热时间、排气时间、抗生素使用时间与对照组相比明显缩短,差异有统计学意义（P〉0.05）;强化血糖控制组术后并发症的发生率2.0%,显著低于对照组13.0%,差异有统计学意义（P〈0.05）。结论：强化血糖控制可改善胃癌合并糖尿病患者术后胰岛素抵抗,减轻术后的炎性反应,降低术后并发症,改善患者预后。     

胃癌合并糖尿病患者术后强化血糖控制的疗效分析

目的:探讨胃癌合并糖尿病患者术后强化血糖控制的临床疗效及其对预后的影响。方法:根据不同血糖控制方法,将96例胃癌合并糖尿病术后患者分为强化血糖控制组50例(血糖控制在4.4-6.1mol/L)和对照组46例(血糖控制在6.1~11.1mol/L)。监测患者术后1、3、7天的空腹血糖(FBG)、空腹胰岛素定量(FINS)、及C反应蛋白(CRP)水平,并计算胰岛素抵抗指数(HOMA-IR),比较分析两组术后恢复情况及并发症发生情况。结果:术后1、3、7天,强化血糖控制组FBG、lnHOMA-IR及CRP水平均显著低于对照组,差异有统计学意义(P<0.05);术后1天两组间FINS水平差异无统计学意义(P>0.05),而术后3、7天,二者之间差异有统计学意义(P<0.05);强化血糖控制组术后发热时间、排气时间、抗生素使用时间与对照组相比明显缩短,差异有统计学意义(P>0.05);强化血糖控制组术后并发症的发生率2.0%,显著低于对照组13.0%,差异有统计学意义(P<0.05)。结论:强化血糖控制可改善胃癌合并糖尿病患者术后胰岛素抵抗,减轻术后的炎性反应,降低术后并发症,改善患者预后。     

Effect of Metformin Therapy on Vitamin D and Vitamin B12 Levels in Patients with Type 2 Diabetes Mellitus

ObjectiveTo determine the effect of metformin on 25-hydroxyvitamin D [25(OH)D] and vitamin B₁₂ levels in patients with type 2 diabetes mellitus.MethodsWe performed a retrospective review of medical records of patients treated between 2003 and 2009 at Loyola University Medical Center, Maywood, Illinois, in both ambulatory primary care and endocrinology clinics. The study cohort consisted of 706 patients with type 2 diabetes mellitus who were 20 to 93 years old (mean age, 63 ± 13) and had a mean body mass index of 33.1 kg/m². Of these patients, 42% were treated with metformin, and 34% had been diagnosed with osteoporosis or osteopenia.ResultsPatients taking metformin had statistically significant lower vitamin B₁₂ levels than those not receiving metformin (P < .0001; 95% confidence interval [CI] = − 220 to − 84 pg/mL). No statistically significant difference was found between users and nonusers of metformin in regard to 25(OH)D levels when adjusted for variables (P = .297; 95% CI for mean difference = − 0.7 to 2.2 ng/mL). Metformin use did not adversely affect successful treatment of vitamin D deficiency in this patient population as a whole, nor did it affect the subgroup with osteoporosis (P = .956). The patients with osteoporosis had statistically significant lower baseline 25(OH)D levels in comparison with those without osteoporosis, when adjustments were made for all variables (P = .003; 95% CI = 0.7 to 3.5 ng/ mL).ConclusionThis study confirms the higher prevalence of vitamin B₁₂ deficiency in metformin-treated patients with type 2 diabetes than in those not treated with metformin. This study also suggests that vitamin D deficiency is not a clinical concern among metformin-treated patients with type 2 diabetes and that metformin does not negatively affect treatment of vitamin D deficiency in these patients. (Endocr Pract. 2012;18:179–184)     

Effect of Hospital Admission on Glycemic Control 1 Year After Discharge

ObjectiveTo assess the effect of hospital admission on glycemic control in patients with diabetes up to 1 year after discharge.MethodsWe retrospectively studied 826 adults with diabetes admitted to a tertiary care medical center and with available hemoglobin A_1c (A1C) values for 6 months before admission and 1 year after discharge. We compared them with 826 nonhospitalized adults with diabetes matched for age, sex, race, comorbidity, and baseline A1C level. We determined the change in A1C value relative to hospitalization and baseline A1C level by using multivariate random effects models for repeated measures. Logistic regression analysis was performed to determine predictors of achieving recommended A1C levels at 1 year.ResultsPatients with baseline A1C levels ≥ 9% had an adjusted rate of change in A1C value of − 0.10% per month (95% confidence interval [CI], − 0.18 to − 0.022; P = .012) during the course of 1 year, without significant differences between hospitalized and nonhospitalized patients in the mean rate of change. Hospitalized patients, however, were less likely to achieve an A1C goal of ≤ 7% at 1 year (odds ratio, 0.68; 95% CI, 0.55 to 0.86; P < .001) or an A1C of < 8% at 1 year (odds ratio, 0.62; 95% CI, 0.48 to 0.81; P < .001) in comparison with the nonhospitalized patients.ConclusionDespite an overall trend toward improved glycemia over time, hospitalized patients with uncontrolled diabetes were less likely to achieve glycemic targets at 1 year in comparison with matched nonhospitalized patients. These results suggest a missed opportunity to improve long-term glycemic control in hospitalized patients with diabetes. (Endocr Pract. 2012;18:456-463)     

Effect of Vitamin D3 Supplementation on Inflammatory Markers and Glycemic Measures among Overweight or Obese Adults: A Systematic Review of Randomized Controlled Trials

BackgroundObesity induced low-grade chronic inflammation disrupts proper immune and metabolic function. Vitamin D deficiency increases inflammation, which is associated with cardiometabolic risk. This systematic review examines the association between oral vitamin D (VD) supplementation and circulating inflammatory biomarkers and glycemic outcomes from randomized controlled trials (RCTs) of overweight and/or obese adults.MethodsMEDLINE OVID, EMBASE and the Cochrane Central Register of Controlled Trials were searched according to a predefined protocol. Eligible RCTs included adults randomized to receive either oral VD or placebo. Two reviewers independently assessed RCTs for inclusion. Bias was assessed using the Cochrane Collaboration risk of bias tool. Mean differences were calculated comparing end-of-study sample means between the independent VD and placebo groups.ResultsEleven unique RCTs met inclusion criteria from a total of 3,383 identified citations, including 79 screened articles and 14 full text data extractions. Inflammatory and glycemic measures were reported in 7 and 10 RCTs, respectively. Most trial findings were non-significant with considerable heterogeneity in design, participants and outcomes. All but one trial was rated as either high or unclear risk of bias. Two RCTs reported significant changes in inflammatory biomarkers; however, the mean difference between groups was not statistically significant: C-reactive protein 0.19 mg/L (p = 0.88); Tumor Necrosis Factor -0.54 pg/ml (p = 0.20). Two other trials found significant mean differences in fasting plasma glucose -0.32 mmol/L (p = 0.03), Hemoglobin A1c -0.13% (p = 0.04), and Homeostatic Model Assessment -0.86 (p = 0.02) following VD supplementation.ConclusionsOverall, there is no clear established benefit of VD supplementation on inflammatory biomarkers among overweight/obese adults. Baseline serum VD possibly influences the effect of VD repletion on inflammatory markers. Risk of bias was present in most studies, thus supporting the need for higher quality studies in this area to more conclusively understand the role VD supplementation has on inflammatory pathways.     

Safety of Vitamin D Replacement in Patients with Primary Hyperparathyroidism and Concomitant Vitamin D Deficiency

ObjectiveTo evaluate the safety of vitamin D replacement in patients with vitamin D deficiency and primary hyperparathyroidism.MethodsRetrospective chart review of 35 patients from our endocrine clinic, age 22 to 89 years, diagnosed with primary hyperparathyroidism and vitamin D deficiency, and treated with either 1,000 to 2,000 international units (IU) of vitamin D daily or 50,000 IU of vitamin D weekly for 5 months. Data were collected before and after treatment on serum calcium, 25-hydroxyvitamin D (25-OH D), intact parathyroid hormone (iPTH), phosphorus, alkaline phosphatase, nephrolithiasis, fractures, and osteoporosis.Results25-OH D increased significantly, from a baseline of 14.65 ± 6.57 ng/mL to 42.17 ± 12.98 ng/ mL after weekly treatment with 50,000 IU of vitamin D (P<.0001), and from 22.42 ± 5.47 ng/mL to 33.33 ± 6.39 ng/mL following daily treatment with 1,000 to 2,000 IU of vitamin D (P<.0001). Pre- and posttreatment unadjusted serum calcium remained stable in the high-dose group (10.80 ± 0.43 mg/dL vs. 10.72 ± 0.67 mg/dL; P = .47), but decreased slightly in the low-dose group (10.76 ± 0.58 mg/dL vs. 10.11 ± 0.54 mg/dL; P = .0007). After adjusting for age, sex, vitamin D, and PTH levels, the small calcium difference in the low-dose group became statistically insignificant. Treatment with either high or low doses of vitamin D did not significantly change iPTH levels. Creatinine remained stable in all patients, and no new cases of nephrolithiasis were reported.ConclusionReplacing vitamin D in mild primary hyperparathyroidism is safe, effective, and does not increase calcium to dangerous levels. (Endocr Pract. 2013;19:420-425)     

Vitamin D Deficiency in a Multiethnic Healthy Control Cohort and Altered Immune Response in Vitamin D Deficient European-American Healthy Controls

Objective

In recent years, vitamin D has been shown to possess a wide range of immunomodulatory effects. Although there is extensive amount of research on vitamin D, we lack a comprehensive understanding of the prevalence of vitamin D deficiency or the mechanism by which vitamin D regulates the human immune system. This study examined the prevalence and correlates of vitamin D deficiency and the relationship between vitamin D and the immune system in healthy individuals.

Methods

Healthy individuals (n = 774) comprised of European-Americans (EA, n = 470), African–Americans (AA, n = 125), and Native Americans (NA, n = 179) were screened for 25-hydroxyvitamin D [25(OH)D] levels by ELISA. To identify the most noticeable effects of vitamin D on the immune system, 20 EA individuals with severely deficient (<11.3 ng/mL) and sufficient (>24.8 ng/mL) vitamin D levels were matched and selected for further analysis. Serum cytokine level measurement, immune cell phenotyping, and phosphoflow cytometry were performed.

Results

Vitamin D sufficiency was observed in 37.5% of the study cohort. By multivariate analysis, AA, NA, and females with a high body mass index (BMI, >30) demonstrate higher rates of vitamin D deficiency (p<0.05). Individuals with vitamin D deficiency had significantly higher levels of serum GM-CSF (p = 0.04), decreased circulating activated CD4⁺ (p = 0.04) and CD8⁺ T (p = 0.04) cell frequencies than individuals with sufficient vitamin D levels.

Conclusion

A large portion of healthy individuals have vitamin D deficiency. These individuals have altered T and B cell responses, indicating that the absence of sufficient vitamin D levels could result in undesirable cellular and molecular alterations ultimately contributing to immune dysregulation.     

Effect of Prediabetes on Membrane Bicarbonate Transporters in Testis and Epididymis

The formation of competent spermatozoa is a complex event that depends on the establishment of adequate environments throughout the male reproductive tract. This includes the control of bicarbonate (HCO₃ ^?) concentration, which plays an essential role in the maintenance of extracellular and intracellular pH (pH_i) values. Diabetes mellitus alters pH_i regulation in mammalian cells, mainly by altering the activity of ion transporters, particularly HCO₃ ^?-dependent mechanisms. Yet, little is known about the effects of this pathology and its prodromal stage, prediabetes, on the membrane transport mechanisms of male reproductive tract cells. Herein, we analyzed protein and mRNA levels of the most relevant HCO₃ ^? transporters of the SLC4 family [anion exchanger 2 (AE2), Na⁺-driven Cl^?/HCO₃ ^? exchanger (NDCBE), electrogenic Na⁺/HCO₃ ^? cotransporter 1 (NBCe1), electroneutral Na⁺/HCO₃ ^? cotransporter 1 (NBCn1)] in the testis and epididymis of a prediabetic animal model. Firstly, we identified the HCO₃ ^? transporters of the SLC4 family, in both testicular and epididymal tissue. Secondly, although no alterations were detected in protein expression, mRNA levels of NBCe1, NBCn1 and NDCBE were significantly increased in the testis of prediabetic rats. On the other hand, in the epididymis, prediabetes caused an increase of AE2 and a decrease of NDCBE protein levels. These alterations may be translated into changes of HCO₃ ^? transepithelial epididymal fluxes in vivo, which may represent a threat for sperm survival. Moreover, these results provide evidence of the molecular mechanism that may be responsible for the significant increase in abnormal sperm morphology already reported in prediabetic rats.     

Effect of Vitamin D Therapy on Bone Turnover Markers in Postmenopausal Women with Osteoporosis and Osteopenia

ObjectiveTo (7) assess the rate of reduction in bone turnover with vitamin D and bisphosphonate therapies and (2) evaluate the clinical utility of bone-specific alkaline phosphatase (BSAP) in monitoring treatment response.MethodsWe retrospectively reviewed medical records of patients with newly diagnosed osteopenia and osteoporosis from 2002 to 2009 at Loyola University Medical Center. A cohort of postmenopausal women with hip or spine T-scores of less than -1, normal serum creatinine, and no prior vitamin D or bisphosphonate therapy was divided into vitamin D-deficient (n = 29) and vitamin D-sufficient (n = 13) groups. Vitamin D-deficient patients received high-dose vitamin D, whereas vitamin D-sufficient patients received orally administered bisphosphonates. BSAP levels at baseline and 1 year were compared.Resultsvitamin D therapy in the group with vitamin D deficiency led to a 26.7% decrease in BSAP (P < .01). Bisphosphonate therapy in the vitamin D-sufficient group led to a 32.7% decrease in BSAP (P = .01). The magnitude of BSAP change in the 2 study groups (6.74 ± 6.48 μg ∕ L and 8.72 ± 9.94 μgZL) did not differ significantly (P = .45).ConclusionThe results of this study suggest that correction of vitamin D deficiency in patients with osteopenia and osteoporosis can lead to a decrease in bone turnover as measured by BSAP and that the magnitude of this reduction is similar to that achieved with orally administered bisphosphonates. (Endocr Pract. 2011;17:873-879)